US2984406A - Machine operating electro-dynamically, more particularly for compressing fluid - Google Patents

Description

May 16, 1961 c ussoN 2,984,406

MACHINE OPERATING ELECTRO-DYNAMICALLY, MORE PARTICULARLY FOR COMPRESSING FLUID Filed July 28, 1959 Uit States Patent MACHINE OPERATING ELECTRO-DYNAMI- CALLY, MORE PARTICULARLY FOR COM- PRESSIYG FLUID Andr Chausson, Asriieres, France, assignor to Societe Anonyme des Usin'es Chausson, Asnieres, France, a French company Filed July 28, 1959, Ser. No. 830,090

3 Claims. (Cl; 230-55) The present invention relates to machines comprising a mobile unit connected with resilient members so as to form a vibrant assembly electro-magnetically maintained. This invention applies still more particularly to those machines that comprise a polarized circuit by means of permanent magnets.

The particular embodiment of the machine according to the invention which can find numerous applications, makes it possible to use only one permanent magnet and a single coil supplied with alternating current, so that the manufacture of the machine is extremely simple, as compared with that of those already known.

According to the invention, the machine, whose moving members are connected with receiving elements driven by these moving members, comprises a magnetic circuit having three distinct branches and an armature comprising a curved permanent magnet whose poles are placed, when at rest, opposite spaces separating the three branches of the magnetic circuit, the central branch of this magnetic circuit carrying an exciter coil.

Various other characteristics of the invention will moreover be revealed by the detailed description which follows.

A form of embodiment of the purpose of the invention is shown, by way of non-restrictive example, in the attached drawing.

Figure 1 is a partial sectional elevation, showing a form of embodiment of a device according to the present invention.

Figure 2 is a section taken substantially along line II-II of Figure 1.

Figure 3 is a diagrammatical section, taken approximately along the line III-III of Figure 2.

According to the method of embodiment of the device shown in the drawing, the latter is enclosed in a casing 1, cylindrical, for example, whose ends are closed by means of covers 2, 3. The casing 1 supports internally suspension lugs 4 intended to connect it, by means of springs 5, to a frame designated in its entirety by 6.

Theframe 6, preferably made of non-magnetic metal, is so shaped as to possess great rigidity, and to constitute at one end a plate 7, forming a bearing, against which one of the edges of a resilient leaf 8 is tightened, held by a tightening part 9 connected to the frame 6 by means of suitable members, such as screws and nuts 10.

The other end of the frame 6 is shaped so as to form a chamber 11 divided into two compartments 12, 13 by means of a partition 14 (Figure 3). This latter part of the frame 6 carries, by means of fixing bolts 15 or other suitable tightening members, a part 16 in which cylinders 17, 18 are bored out, respectively emerging in the com partments 12, 13 of the frame 6 and inside the casing 1.

As shown more particularly in Figure 3, the communication between the cylinder 17 and the compartment 13, on the one hand, and the cylinder 18 and compartment 12, on the other hand, is controlled by means of flap-valves 19 and 20 conected to the part 16 by means of holding lugs 21 (Figure 2).

The flap-valves 19 and 20 are provided with caps 22,

22a of elastically deformable flexible material, which appreciably have the shape of a frustrum of a cone so that their peripheric edges press against the walls of the cylinders 17 18.

In the example shown, the cap 22 of the flap-valve 19 is arranged so that its concavity is turned towards the compartment 13, whereas, on the other hand, the cap 22a of the flap-valve 20 occupies the opposite position whereby its concavity is turned towards the cylinder 18.

In addition to the members described above, the frame carries a cradle 23 of non-magnetic material, this cradle being intended to hold a magnetic circuit 24 formed by three distinct branches 25, 26, 27, respectively forming the poles 25a, 26a and 27a.

28 designates a coil threaded on to the central branch 26 of the magnetic circuit. This coil is intended to be supplied with alternating current with fixed frequency by means of conductors 29 connected to terminals 30 carried by the cover 2 closing the casing 1.

As shown, the conductors 29 can be held against the frame 6 by means of a securing part 31. The magnetic circuit described above, which is preferably formed by magnetic sheets properly insulated from each other, is intended to cooperate with an armature 32 comprising an anisotropic permanent magnet which is shaped like a circular are so that its poles 32a, 32b are placed, when the device is at rest, opposite spaces delimited between each of the branches of the magnetic circuit.

As can be seen from the drawing, the magnet 32 is embedded in a part 33, advantageously conductive of current but non magnetic. This part is so shaped as to form a lug 34 acting to effect the fixing of the armature assembly on the free end of the elastic leaf 8.

Furthermore, the armature comprises polar parts 35, 36 of magnetic material. It is advantageous, as shown, that the external face of the polar parts 35, 36, as well as the poles 25a to 2701 of the magnetic circuit 24 should be circular are shaped so that the air-gap delimited between the polar parts of these poles remains constant while the device is in operation, as described hereafter.

The end of the elastic leaf 8 to which the armature 32 is attached, also carries a part 37 having approximately a frame shape whose dimensions are selected so that the lateral sides 38, 39 of this frame (Figure 1) are placed on either side of the magnetic circuit 24.

The end of the frame opposite to that attached to the elastic leaf 8 carries, by means of holding pins 40, 41, rods 42, 43 connected to pistons 44, 45.

In the example shown, the rods 42, 43 are formed of piano wires having a certain amount of flexibility so as to compensate for the respective variations between the axes of the cylinders 17, 18 and the trajectories of the pistons 44, 45.

As can be seen more particularly in Figure 3, the pistons 45, 44 comprise, in the same way as the flap-valves 19, 20, caps 46 and 46a of deformable flexible material and these caps, which are preferably shaped like those of the flapvalves, are so arranged that their concavity is turned in the same direction as that of the flap-valves.

Seeing that the assembly described above is intended to be used as a compressor operating as a double-stage and that the stroke of the pistons 44, 45 must be the same, the diameters of the cylinders 17, 18 are determined in a known manner.

The fluid to be compressed is brought into the compartment 12 through a pipe 47 (Figures 2 and 3). This pipe is advantageously connected to the frame 6 by means of a support 48, the part of the pipe comprised between the support 48 and a ferrule 49 traversing the cover 2 of the casing 1 being shaped like a helix.

In like manner, the compressed fluid, as described hereafter, is forced through a compartment 13, by a pipe 3 50 shaped like the pipe 47. This latter the cover 2 in a connection 51.

The device described above operates as follows:

The elastic leaf 3, as well as the various parts described above which it supports, forms a mobile unit having its own given vibrating frequency which obviously depends upon the resilient characteristics of the leaf and the neutral point of the suspended members.

*In the device described, the frequency belonging to this mobile unit is selected so that it is appreciably lower than the frequency of the alternating current used for supplying the coil 28.

When the device is at rest, as has been described above, the polar parts 35 and 36 of the armature 32 are placed opposite to the spaces delimited between the poles a, 26a, on the one hand, and 26a, 27a, on the other, of the magnetic circuit. The Width of the polar parts 35, 36 is nevertheless selected so that their lateral edges slightly intercept the poles of the magnetic circuit, in order that the lines of force of the permanent polarization field produced by the magnet 32 close across the branches of the magnetic circuit.

In this position of the armature, the edges of the compression pistons 44, 45 are placed appreciably at the middle part of the cylinders 17, 18. When the coil 28 is supplied with alternating current, this has the effect of setting up an equally alternating magnetic field in the midst of the magnetic circuit 2%. Owing to the particular shape of this magnetic circuit, at a given moment t, the pole 26a has a polarity, South, for example, whereas the poles 24a and 27a have a north polarity. Consequently, the armature 32 tends to become displaced in the direction for which a maximum flux is induced in the coil 28.

At the semi-alternation following of the alternating field, the polarities of the poles of the magnetic circuit are inverted so that the armature tends to become displaced in the opposite direction.

As can be seen from the drawing, for all the positions that the armature can occupy in relation to the magnetic circuit, the polar parts 35 and 36 of this armature are always opposite to the magnetic parts, so that the magnetic field is, in this Way, always closed. Moreover, for a complete working cycle, the flux induced in the coil 28 is inverted, so that the total flux variation is set up from a value up to a value of The armature 32 being connected with the elastic leaf 8, it follows that the operational method of the device is that of a system electro-magnetically maintained, which has the advantage of only comprising one polarization magnet and one induction coil.

The alternating movement in which the armature 32 is impelled, as described above, is transmitted by the part 37 to the pistons 44 and 45. When the pistons 44 and 45 are moved in the direction of the arrow f (Figure 3), this has the effect of decanting the fluid into the casing 1 contained in the part of the cylinder 18 situated above the cylinder 44 when the pressure prevailing in that part of the cylinder becomes appreciably equal to the pressure in the casing. Actually, the fluid in that part of the cylinder cannot be forced into the compartment 12, for any increase in pressure has the effect of more strongly applying the flexible cap 22a of the flap-valve 20 against the cylinder wall, whereas any increase in pressure in that part of the cylinder causes the deformation of the flexible cap 46a of the piston 44, thus favourising the decanting of the fluid into the casing. Furthermore, the fluid that is in the part of the cylinder 17 above the piston is compressed and driven by the latter into the compartment 13 forming a discharge chamber, owing to the arrangement of the flexible caps, both of the flap-valve 19 as well as the piston 45.

When, on the other hand, the above-mentioned pistons are moved in a direction opposite to that of the arrow f (Figure 3), the flexible cap 46a of the piston 44 is tightpipe 50 traverses v ened against the cylinder wall 18, so that the fluid is compressed in the casing 1, at the same time that a fresh quantity of'fluid is sucked from the compartment'lZ, because any depression produced in the part of the cylinder defined above as the part above in relation to the piston 44, has the effect of causing the flexible cap of the flap-valve 20 to become deformed, and consequently, of enabling the fluid contained in the compartment 12 to be admitted into the cylinder 18.

During the same time, a part of the fluid already compressed which is in the casing, is decanted into the cylinder 17. The same operative cycle is repeated, and it follows that a first compression stage is obtained by forcing and compressing the fluid into the casing 1, which is obtained by means of the piston 44, whereas the second compression stage is effected by the piston 45 sucking up in the casing 1 and delivering into the compartment 13.

This particular method of working, which ensures for one of the pistons its intake stroke, at the same time that the other piston effects its compression stroke, has the effect of making the reactions of the pistons on the mobile unit more even during the period, so that the amplitude of the pendular movement to which the flexible leaf is subjected is substantially symmetrical in relation to its equilibrium position.

So that the stroke of the pistons cannot exceed a certain degree, it is advantageous to provide the part 37 with a stop 52 which is only used in case of exceptional circumstances, such, for example, as when there are great variations of frequency or voltage clue to a momentary disturbance of the supply system.

It is also interesting to be able to regulate the assembly of the mobile unit, and this is obtained by providing the part 37 with a support member 53 for the additional masses. Moreover, and to prevent the fragile parts of the device described above from striking against the casing, it is advantageous to provide stops 55 on the frame 6 partially engaged in the basins 56 fixed both to the casing 1 as well as to one or other of the covers.

As shown in Figure 1, the casing is also used as a receptacle containing a quantity of lubricant designated by the reference numeral 57, this lubricant being conveyed to the cylinders, by means of rods 58, for example, of sintered material which are partly plunged in the lubricant.

The device can also be provided with various other accessories and it is possible, in particular, to endow it with supplementary cooling members.

The invention is not restricted to the example of embodiment shown and described in detail, for various modications can be applied to it without going outside of its scope. In particular, the cylinders 17, 18 can be placed one above the other. Likewise, the compressor can be single-staged. Furthermore, in certain cases, the semi-circular permanent magnet can be replaced by one or more rectilinear magnets one in relation to the other, and possibly in relation to magnetic cylinder-heads so that the lines of force of their field follows the same course as that defined above in connection with the magnetic circuit.

I claim:

1. In an electromagnetic pump or compressor device, the combination of a frame having a plate at one end and a housing at the other end, a resilient blade secured by one end to said plate of the frame, an armature assembly of conducting but nonmagnetic material secured to a second end of said resilient blade, an arcuate permanent magnet embedded into said armature assembly from which both ends of said magnet protrude, a magnetic circuit having three poles secured to said frame so that said poles are located in front of said protruding ends of the magnet from which they are separated by a thin air gap, an AC. supplied coil winding fitted onto one of said poles, a cylinder block secured to said one end of the frame which delimits a housing, at least one piston slidably mounted in said cylinder block, and a connecting member surrounding said magnetic circuit and rigidly connected both to said resilient blade and to said piston by means of a flexible piston rod.

2. A device as set forth in claim 1 wherein the protruding ends of the permanent magnet are provided with armate polar parts, and the poles in front of said permanent magnet are provided with terminal walls shaped correspondingly to said arcuate polar parts.

3. A device as set forth in claim 1 comprising a fluid tight tank in which said device is resiliently mounted, the cylinder block being provided with two cylinders of different diameters respectively in communication with two 6 distinct chambers delimited inside said housing of the frame and with the inside of said tank, a piston in each cylinder respectively arranged so as to work oppositely, and inlet and outlet ducts respectively in communication 5 with said two chambers.

References Cited in the file of this patent UNITED STATES PATENTS 10 2,521,653 Ruud Sept. 5, 1950 FOREIGN PATENTS 1,177,892 France Dec. 8, 1958

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