JPH025105Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a cylinder for an electromagnetic reciprocating compressor, in particular, it eliminates the trouble of alignment during assembly, has good power efficiency during compressor operation, and has good heat dissipation. Regarding the cylinder of a good electromagnetic reciprocating linear compressor.

(Prior Art) An example of a conventional electromagnetic reciprocating compressor is described in, for example, Japanese Patent Application Laid-Open No. 53-30011.

In this electromagnetic reciprocating compressor, the main piston and the sub-piston provided at the rear with the armature in between are inserted into a cylinder divided into front and rear parts to prevent uneven wear of the main piston. are connected with screws with the field core in between. Further, the cylinder is made of aluminum material and is surface-treated with hard alumite in order to insulate it. The piston and armature, which are integrally coupled and housed inside the cylinder, are biased toward top dead center by a spring. Furthermore, an induction coil is disposed on the field core to supply magnetic flux to the field core and armature.

Now, when power is supplied to the induction coil at a predetermined timing and the field core is excited, the armature is attracted to the field core. When the power supply is stopped when the piston reaches the bottom dead center, the force of the field core to attract the armature disappears, and at this time, the piston receives the force of the spring and returns to its original position.

When such operations are repeated, the piston reciprocates within the front cylinder and a predetermined fluid compression effect is achieved.

(Problems to be Solved by the Invention) The cylinder of the conventional electromagnetic reciprocating compressor mentioned above is made of aluminum insulated with hard alumite, but if there is even a slight insulation defect, For example, even if there is poor insulation in the connecting threads of the front and rear cylinders, when the magnetic flux output from the field core is input, eddy currents will also be generated in the aluminum rear cylinder, and the applied electrical energy will be There was a problem that there was a loss. Furthermore, since the cylinder is made up of two parts, it is difficult to create an acceptable alignment dimension accuracy for both parts, and it is necessary to connect the two parts with screws, so assembly requires skill. The problem was that it was expensive.

(Means and effects for solving the problems) The feature of the present invention is that the front and rear cylinders of the electromagnetic reciprocating compressor are integrally molded with an electrical insulator to eliminate loss of electrical energy and to maintain the center of gravity. The point is to make it easier.

(Example) The present invention will be explained below using examples.

1, 2, and 3 are diagrams for explaining a cylinder used in an electromagnetic reciprocating compressor according to an embodiment of the present invention. Figure 1 is a perspective view, Figure 2a is a cross-sectional side view of the cylinder, Figure 2b is
Figure 1c shows a front view, figure c shows a rear view, and figure d shows a plan view. 3a is a sectional view taken along the line A-A in FIG. 2a, FIG. 3b is a sectional view taken along the B-B line, and FIG. FIG.

As is clear from FIGS. 1 and 2, the cylinder 2 of the present invention has a rear cylinder 3a, a front cylinder 3b, a piston shaft guide boss 4, and a flange 8 of integral structure, and is made of an insulating material, preferably a thermally expandable material. It is made of a synthetic resin such as polyamideimide, which has a coefficient similar to that of aluminum. A piston shaft guide hole 6 having an axis coincident with the axis of the cylinder 2 is formed in a piston shaft guide boss 4 provided at the axis of the rear cylinder 3a toward the front cylinder 3b. The flange 8 is formed with a screw hole 10 into which a screw for fixing a field core, which will be described later, is inserted. A spigot portion 12 is formed on an end surface 3b' of the front cylinder 3b that faces the rear wall surface 3a' of the rear cylinder 3a. Further, a flange 14 for fixing a cover 3 for forming a cylinder head (see FIG. 4a) is integrally molded at the open end of the cylinder 3b. Furthermore, between the flange 8 and the front cylinder 3b,
A reinforcing rib 16 is provided to make the right side portion of the flange 8 (FIG. 2a) completely orthogonal to the axis of the cylinder 2.

The cross-sectional shapes of the front cylinder 3b and the rear cylinder 3a are different as shown in FIGS. 3a and 3b, respectively. That is, A-A in Figure 2a
The cross-sectional shape along the line is a perfect circle inside, and the outer wall surface is chamfered with a plane parallel to the central axis and symmetrical to the center. On the other hand, the cross-sectional shape taken along the line B-B in the figure has two chamfers parallel to the chamfered surface of the front cylinder 3b, and the inside and outside of the rear cylinder 3a communicate with each other through the notch 5. There is. The circular arc forming the inner wall surface of the rear cylinder 3a has substantially the same radius of curvature as the inner wall surface of the front cylinder 3b, and forms a curved surface that is substantially the same as the inner wall surface of the cylinder 3b.

In addition, in FIG. 2, 20 is a valve seat, and the fourth elastic valve 30 for intake provided on this valve seat 20
(see Figure a) is fixed by the lid 31. 18 in FIG. 3c is an exhaust hole. Further, the exhaust hole 18 has a duck-bill type discharge valve 33 which has excellent sealing properties and can obtain stable rated pressure.
(see FIG. 4 d) is fitted, and a discharge pipe 34 (see FIG. 4 d) is connected to the discharge portion accommodating the valve 33.

Next, the structure of a compressor equipped with the cylinder 2 of the present invention will be explained with reference to FIG.

4A is a longitudinal sectional view of the compressor, FIG. 4B is a front view, FIG. 4C is a rear view, and FIG. 4D is a plan view. In these figures, the same reference numerals as in FIGS. 1 to 3 indicate the same or equivalent parts.

Now, as shown in FIG. 4, inside the cylinder 2 are an armature 24 and a piston 26.
A piston assembly including a piston shaft 28 and a piston shaft 28 is housed therein. The armature 24 and the piston 26 have center holes, and the piston shaft 28 has a small diameter part and a large diameter part, and by press-fitting the small diameter part into both the center holes of the armature 24 and the piston 26, The three members of the shaft are designed not to separate.
The large diameter portion of the piston shaft 28 is connected to the piston shaft guide hole 6.
It is slidably inserted into the holder with extremely tight fit tolerances. Therefore, the piston shaft guide hole 6 of the rear cylinder 3a of the cylinder 2 and the inner wall surface of the front cylinder 3b serve as bearings at the front and rear of the piston sliding surface. Further, a spring 22 disposed around the large diameter portion is attached to the armature 2.
4 and the piston 26, etc., is urged toward the left end of the front cylinder 3b in FIG. 4a, that is, toward the top dead center.

The intake valve 30, which is fixed between the front opening end of the front cylinder 3b and the cylinder head forming lid 31 that closes the front end, has the piston 26 on the right side in FIG. 4a. That is, when moving toward the bottom dead center, the intake pipe 32 opens.
Fluid, such as air or liquid, sent through is introduced into the working chamber formed by the front cylinder 3b, the piston 26, the lid 31, and the like. Conversely, when the piston 26 moves toward the left in FIG.

In FIG. 4a, 36 is the field core 38
The screw 40 for fixing the to the cylinder 2 of the present invention is an induction coil attached to the magnetic poles 42, 42 of the field core 38. Further, 51 indicates a mounting frame having four anti-vibration rubbers 50. The mounting frame 51 is fixed to both the front and rear surfaces of the field core 38 with screws 52. Further, 54 in FIG. 4b indicates a rectifier.

FIG. 5a is a perspective view of the field core 38,
Figure b shows its plan view, and figure c shows its cross-sectional view. The field core 38 has a pair of left and right magnetic poles 4.
2, 42, and a cutout spigot part 44 is formed on the front surface of the distal end arc edge of the opposing part. After the induction coil 40 is attached and fixed to the coils 42, 42, the field core 38 is attached with the spigot part 44 facing the spigot part of the front cylinder 3b. At this time, the magnetic poles 42, 4
2 are inserted into the rear cylinder 3a while facing each other through the left and right notches 5, 5 of the rear cylinder 3a.

When the field core 38 is inserted to its deepest point, i.e., closest to the front cylinder 3b as shown in FIG. and the spigot part 44 engages with the spigot part 12 (see FIGS. 1 and 2a) of the front cylinder 3b. Therefore, the center of the cylinder 2 and the center of the field core 38 can be easily aligned. Thereafter, the screw 36 is inserted into the hole of the flange 46 of the field core 38, and then the same screw 36 is screwed into the screw hole 10 of the flange 8 of the cylinder 2, so that the cylinder 2 and the field core 38 are fixed together. be done.

Now, in the electromagnetic reciprocating compressor mentioned above,
When half-wave alternating current of an appropriate frequency is applied to the induction coil 40, the field core 38 is excited at time intervals corresponding to the frequency. When the field core 38 is energized, the armature 24 is attracted to the magnetic pole 42 of the field core 38, so that the piston 26 moves against the spring 22 and moves to the fourth position.
It moves to the right in figure a and is brought to the bottom dead center position. On the other hand, when the excitation of the magnetic pole 42 is turned off, the armature 24 is released from the magnetic pole 42. At this time, the piston 26 is moved to the top dead center position by the restoring force of the spring 22.

When the above operations are performed continuously, the compressor performs a predetermined operation. Even if heat is generated during operation, the rear cylinder 3a of the cylinder of the present invention is provided with notches 5, 5 that communicate between the inside and the outside, and this notch allows the piston assembly to remain a part of the piston assembly. Since the armature is exposed to the outside, the cooling effect is great. Furthermore, if the vibration-proof rubber mounting frame 51 and the field core 38 are mechanically fixed together, the mounting frame can function as a cooling fan without increasing the surface area of the field core, and the cooling effect can be further improved. growing.

In this example, polyamide-imide was used as the material for the cylinder 2, but the piston 2
Of course, other materials may be used as long as they are non-magnetic insulators having a coefficient of thermal expansion close to those of the armature 6 and the armature 24.

(Effects of the invention) (1) According to the invention, since the front and rear cylinders are integrally molded with an insulator, no eddy current is generated in the cylinder due to the magnetic flux output from the magnetic pole of the field core, and electric energy is A highly efficient compressor with no loss can be provided.

(2) Since the front and rear cylinders are integrally molded, it is no longer necessary to assemble the front and rear cylinders, which were formed individually, with screws while paying attention to their alignment, as in the past. Therefore, conventional work processes that require skill can be reduced and manufacturing can be done at low cost.

(3) Since the rear cylinder has a notch, heat does not get trapped inside the cylinder, and heat radiation efficiency is high.

(4) Since the piston is supported on both the front cylinder and the piston shaft guide boss, even if an asymmetrical magnetic force acts on the armature with respect to its axis, it will not be drawn toward the magnetic pole side where the magnetism is stronger. , can prevent uneven wear of the piston.

[Brief explanation of drawings]

Figure 1 is a perspective view of one embodiment of the present invention, Figure 2 a
The cylinder is a sectional side view, FIG. B-B in Figure 2 a
A cross-sectional view along the line C--C in FIG. 2a,
Figure 4a is a vertical sectional view of the cylinder shown in Figures 1 to 3 with the piston and electromagnetic device attached, Figure b is its front view, Figure c is its rear view, and Figure 4d is its plane. 5A is a perspective view of the field core, FIG. 5B is a front view thereof, and FIG. 5C is a sectional view taken along line A--A. 2... Cylinder, 3a... Rear cylinder, 3b
...Front cylinder, 4...Piston shaft guide boss, 5...Notch, 8...Flange, 10...Screw, 31...Cylinder head forming cover.

Claims (1)

[Scope of utility model registration request] A front cylinder whose inner circumferential wall surface has a cylindrical shape and a piston insertion opening in the head part, and a field core on a symmetrical plane that is concentric with the front cylinder and parallel to the axis of the front cylinder. a rear cylinder that has a notch that exposes the left and right magnetic poles and is continuous and integral with the front cylinder; and the front cylinder that is formed at an end of the rear cylinder toward the front cylinder. It consists of a concentric piston shaft guide boss, and a radially extending field core fixing flange provided on the outside of the front cylinder near the boundary with the rear cylinder, and these front and rear cylinders and the flange are connected electrically. An electromagnetic reciprocating compressor cylinder characterized by being integrally molded with an insulating material.