US 3342254 A
Description (OCR text may contain errors)
.Kumo .FUJIE 3,342,254 VENTILATING MACHINE OF SUPPLY-EXHAUST TYPE WITH HEAT EXCHANGER Fild Sept. 1, 1965 g 2 Sheets-Sheet 1 Fl-6.1m)
FIG. 1(a)" INVENTOR. K bl NIIO PU. M E
JJ. Wi /M Filed Sepf. 1, 1965 Sept l9, 19 67 -KUN|Q FUJIE 3,342,254
VENTILATING MACHINE OF SUPPLY7EXHAUST TYPE WITH HEAT EXQHANGER 2 Sheets-Sheet 2 FIG. 3( FIG. an
STATIC PRESSURE H (mm Aq) FIG; 5
INVENTOR. Kumo F LJiE United States Patent 3,342,254 VENTILATING MACHINE 0F SUPPLY-EXHAUST TYPE WITH HEAT EXCHANGER Kunio Fujie, Tokyo-to, Japan, assignor to Kabushiki Kaisha Hitachi Seisakuslro, Chiyoda-ku, Tokyo-to, Japan, a joint-stock company Filed Sept. 1, 1965, Ser. No. 484,299 Claims priority, ap lication Japan, Sept. 2, 1964, 39/ 49,888 3 Claims. (Cl. 1658) ABSTRACT OF THE DISCLOSURE apparatuses and to heat exchangers. More particularly, the invention relates to a new ventilating machine of the supply-exhaust type capable of simultaneously delivering air or gas streams in mutually opposite directions with a blade rotor (or runner) and, moreover, of accomplishing heat exchange at the same time between the air streams of opposite flow directions by means of a thermal regenerative matrix.
In general, conventional machines such as fans of the axial-flow type and centrifugal type for blowing air and gases are capable of blowing a gas in only one direction, and one of these machines is incapable of accomplishing both forced supplying and exhausting of, for example, air in the case where air within a room is to be exhausted to the outside, and the outside air is simultaneously to be drawn into the room. Accordingly, in air-conditioning equipment and ventilating equipment requiring such simuL taneous supplying and exhausting of air, it has heretofore been the common practice to use separate fans respectively for supplying and exhausting air.
This practice naturally necessitates a large installation space and unavoidably becomes disadvantageous particularly in cases of installation in places such as residential houses where installation spaces are limited.
Furthermore, in the case of air-conditioning equipment and cooling and heating equipment in which simultaneous supplying and exhausting of air is required, it is obviously necessary for the purpose of improving heat economy to utilize heat effectively by causing heat exchange between the outside air introduced into the room and the room air to be exhausted; However, in conventional equipment requiring two fans for supplying and exhausting air, it is difiicult to construct compactly the parts for heat exchange between the currents of supply and exhaust air, whereby the required installation space unavoidably becomes even larger.
It is a general object of the present invention to overcome the above described difiiculties.
More specifically, an object of the invention is to provide a ventilation machine of the supply-exhaust type based on a new concept and method whereby, with a single blade rotor, supplying and exhausting of air or a gas can be simultaneously accomplished, and heat exchange between the supply and exhaust air or gas can be l the terms concave and convex accomplished at the same time by means of a thermal regenerative matrix disposed coaxially with the rotor.
According to the present invention, briefly stated, there is provided a gas ventilating machine of the supply-exhaust type comprising a cylindrical duct with an interior divided into two flow passages by a fiat partition extending in parallel to the duct axis along the length of the duct except for duct sections where rotating parts are positioned; a rotor with blades shaped in concave for-m, seen from the revolving direction of the rotor, and supported coaxially and rotatably with the duct in said duct section; guide vane assemblies respectively disposed near both axial ends of said rotor, one of which has vanes shaped concave and convex, respectively, when seen from the revolving direction of the rotor in each of the two flow-passages, and the other having vanes in opposite direction to the curvature of the first, whereby said rotation of the blade rotor causes gas flows in the two flow passages in mutually opposite directions, and/or means to promote heat exchange between said gas flows.
The nature, principle, and details of the invention Will be more clearly apparent from the following detailed description with respect to preferred embodiments of the invention, when read in conjunction with the accompanying drawings in which like parts are designated by like reference numerals, and in which:
FIG. 1(a) is a side view of the interior of the ventilating machine of the present invention to indicate the shape and arrangement of the blades on the assumption that the cylindrical duct and the boss are transparent. FIG. 1(b) is a cross sectional view taken along the plane indicated by line 1b 1b in FIG. 1(a);
FIG. 2 consists of three perspective views showing the construction of rotating blades and rotor (FIG. 2(a)) and guide vanes (FIGS. 2 (d) and 2(e)) suitable for use in the ventilating machine of the invention;
FIGS. 3( and 3(g) are respectively a side view with a part cut away and a longitudinal sectional view showing an embodiment of the ventilating machine according to the invention;
FIG. 4 is a graphical representation, based on experimental results, indicating the relationship between air fiowrate arid static pressure at various rotor speeds in one example of the ventilating machine of the invention; and
FIG. 5 is a longitudinal sectional view showing another embodiment of the invention.
Referring to FIG. 1 indicating the principle of the invention, the ventilation machine based thereon is generally installed within a duct 1 or like structure of circular cross section and comprises essentially a blade rotor 2 having blades 6 and rotated by a prime mover such as an electric motor (not shown), guide vane assemblies 3 and 4 fixed to the inner wall of the duct 1 on the two sides of the rotor 2, and a flat partition 5 dividing the interior of the duct 1 into two flow passages 88a and 99a.
The rotor 2 comprises several blades 6 of arcuate profile fixed radially to a boss 7 and of concave form as seen from the direction of the revolving rotor (hereinafter, are to be understood to be seen from that direction), as shown in FIGS. 1(b) and 2(a). The guide vane assemblies 3 and 4 also have radial vanes with curved profiles, but in each assembly the convexities of the vane face on one side of the fiat partition 5 is opposite to that on the other side thereof as shown in FIGS. 1(a), 2(d) and 2(e). Moreover, the configuration of the vane assembly 3 is opposite to that of guide vane assembly 4, as shown in FIGS. 1(a), 2(d) and 2(e).
Fluid dynamical consideration of the operation of the ventilating machine of the above described construction will be described below in a simplified manner with reference to FIG. 1(a).
When the rotor 2 is rotating at a peripheral velocity u in the direction of the arrow in FIG. 1(a), the absolute velocity v of the air within the guide vane assembly 3 on the right-hand side of the partition has the direction indicated since the vanes 3 have the configuration as shown. Therefore, from the resultant velocity triangle, the relative velocity w of the air within the guide vane assembiy 3 with respect to the rotor 2 has the direction indicated in FIG. 1(a).
On the other hand, the air within the guide vane assembly 4 has an absolute velocity 1 since the vanes 4 have the configuration shown. Therefore, from the resultant velocity triangle, the relative velocity w of the air within the guide vane assembly 4 with respect to the rotor 2 may be considered to have the direction shown.
As is apparent from FIG. 1(a), the direction of the relative velocity w of the air within the guide vanes 3 is approximately the same as the direction of the upper leading edge of the blades 6, but the direction of the relative velocity w,, of the air within the vanes 4 is substantially different from that of the lower leading edge of the blades 6. For this reason the resistance to the fiow of air from the guide vanes 4 into the rotor 2 becomes greater than that of air from the guide vanes 3. Consequently, the air flows from bow passage 8 toward flow passage 8a, and a velocity component w, from the guide vanes 4 toward the rotor 2 as indicated in FIG. 1(a) cannot exist.
In the flow passage 99a on the other side of the partition 5, the air flows from 9 toward 9a for the same reason, whereby a counterflow state is established in the flow passages 9-9a and 3-8a. That is, it is possible to supply air simultaneously in opposite directions by means of a single rotor 2.
The angles of the edges of the guide vanes 3 and 4 and the blades of the rotor 2 of the ventilating machine of the invention as described above vary, depending on the fluid to be propelled, but in the case of air, angles substantially as indicated in FIG. 1(a) are recommended.
In a specific embodiment of the invention as shown in FIG. 3, a regenerative matrix is incorporated in the structure of the ventilating machine shown in FIG. 1, and heat exchange is caused between the oppositely flowing streams of air. The rotor 2 is driven by amotor 10 mounted in the boss 12 of the guide van assembly 4 and fixed thereto by bolts 13. The guide vane assembly 4 is fixed by bolts 11 to the duct 1. The boss 7 of the rotor 2 is fixed by a key 15 to the rotor shaft 14 of the motor 10, the rotor 2 being rotated in the direction of the arrow shown in FIG. 3(f).
A regenerative matrix 16 of mesh form made of metal Wire such as copper, aluminum, or iron wire is interposed between the blades 6 of the rotor 2 and greatly promotes the heat exchange between the streams of air caused by the rotation of the rotor 2 to flow in opposite directions in the flow passages 8-8a and 9-911. More specifically, the regenerative matrix 16 is heated, for example, by the air flowing through the passage 8-8a and, as it rotates, releases the heat stored therein to the air flowing through the passage 9-901, whereby simultaneously with the supplying of air in opposite directions, it is possible also to accomplish automatic heat exchange between the two air streams.
In one experimental example, the essential details of a ventilating machine according to the invention were as flows: number of blades on rotor 2, twenty; axial dimension t (as shown in FIG. 3 (g)) of rotor 2, 15 mm; diameter d of rotor, 150 mm.; number of vanes of each guide vane assembly, twenty; axial dimension l,,, of each guide vane assembly, 5 mm.; axial dimension l of regenerative matrix 16, 7.5 mm; and edge angles of blades and vanes as indicated in FIG. 1(a). When this ventilating machine was operated at a rotor rotational speed of 1,500 rpm. with a temperature difference of 20 degrees C. at the inlets of the air streams flowing in opposite directions, a tem- Cit perature difierence of approximately 10 degrees C. was obtained at their outlets.
The relationships of air flowrate Q and static pressure H at various rotor speeds of the above described ventilating machine supplying air streams of equal flowrate in opposite directions are indicated by the Q-H characteristic curves shown in FIG. 4. The utility and practical nature of this supply-exhaust ventilating machine as indicated by the aforedescribed fluid dynamical consideration are apparent also from these experimental results.
In another embodiment of the invention as shown in FIG. 5, the feature in which it differs from the example shown in FIG. 3 is the disposition of the mesh-form regenerative matrix 16, which, as shown in FIG. 5, is fixed to the rotor shaft 17 of the rotor 2 at a position on the outer side of one (4) of the guide vane assemblies.
By this construction, the removal or replacement of the mesh-form regenerative matrix 16 from the outside is greatly facilitated, whereby, in the case when foreign substances such as dust are adhering to the matrix 16, it can be readily removed and cleaned. In this example, the motor 10 is supported by support members 18 fixed by bolts or screws 19 to the duct 1. In the construction illustrated in FIG. 5, furthermore, the use of flanged ends of the duct 1 to form a unit product affords great convenience and adptability for suitable attachment to walls or other ducts.
As is apparent from the above description, the present invention provides a supply-exhaust ventilating machine capable, with a single rotor, of simultaneously supplying air streams in mutually opposite directions and, at the same time, causing heat exchange between these air streams by the use of a regenerative matrix rotating coaxially with the rotor. Accordingly, the present invention is highly effective and advantageous when applied to equipment requiring ventilation for air conditioning and heating and cooling of spaces thereby to accomplish simultaneous ventilation and heat exchange in an efiicient manner.
Furthermore, the ventilating machine according to the invention requires much less space, more specifically, of the order of from /3 to /2, of that required by conventional equipment for performing the same functions with the same air fiowrate and same heat-exchanging performance.
Another advantage, which cannot be neglected, is the sound-proofing afforded by the mesh-form regenerative matrix when it is positioned on the inner side, or room side, of the moving parts. In the case where the regenerative matrix is to be mounted on a shaft separately from the blade rotor, it is preferable to reduce the rotational speed of the matrix by means such as gears to approximately 10 to 50 rpm. thereby to reduce mixing of the high-temperature and low-temperature gases.
It should be understood, of course, that the foregoing disclosure relates to only preferred embodiments of the invention and that it is intended to cover all changes and modifications of the examples of the invention herein chosen for the purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention as set forth in the appended claims.
What I claim is:
1. A gas ventilating machine of the supply-exhaust type comprising a cylindrical duct with an interior divided into two flow passages by flat partitions extending in parallel with the duct axis along the length of the duct except for duct sections where rotating parts are positioned; a blade rotor fitted with blades wherein the blade face is concave and the blades are supported rotatably and coaxially with the duct in said duct section; means to drive said blade rotor in rotation in one direction; and guide vane assemblied respectively disposed near both axial ends of said blade rotor and having radial vanes with curved profiles, the curvature of the vane face on one side of the partition being opposite to that on the other side of the partition,
5 and the curvature of the vane face in each of said guide vane assemblies being opposite each other.
2. The gas ventilating machine as defined in claim 1, wherein a mesh-form thermal regenerative matrix is provided in, and rotates with, said blade rotor.
3. The gas ventilating machine as defined in claim 1, wherein a mesh-form matrix is provided, rotating in said duct section, driven by the rotation of said blade rotor.
References Cited UNITED STATES PATENTS Parrish 230122 Ballard 1658 Spalding 23069 Helmbold 230133 Bakos 230-47 FOREIGN PATENTS France.
DONLEY J. STOCKING, Primary Examiner. HENRY F. RADUAZO, Examiner.