JPH0480237B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a fluid machine such as a pump or a compressor used for transporting incompressible fluid or compressible fluid, and particularly to a fluid machine that is rotationally driven by a prime mover. The present invention relates to a so-called reciprocating piston type compressor that converts rotational motion of a shaft into reciprocating motion of a piston, and causes a fluid conveying action by the reciprocating motion of the piston.

[Prior Art] A conventional fluid machine of this type having a reciprocating piston is disclosed in US Pat. No. 3,781,135 (Filed: May 19, '72: Inventor; Claude H.
As shown in Nike-11), the cylinder is usually fixed.

For this reason, the crank mechanism that converts the rotational motion of the shaft into the reciprocating motion of the piston is complex and has a large number of parts, resulting in a large capacity occupied by the compressor.

In contrast, US Pat. No. 3,200,797 (Filed; Aug 29, '62: Inventor; Horst
Dillenberg), in the field of internal combustion engines, the cylinder to which the piston slides is configured to rotate within the outer shell of the aircraft body, and the cylinder itself is used to convert the reciprocating motion of the piston into rotational motion of the shaft. It is known to simplify the structure of the crank mechanism by also using it as part of the crank mechanism.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a reciprocating piston type fluid machine with a simple crank mechanism structure, a small number of parts, and a small volume occupied by the crank mechanism.

[Summary of the invention]

A feature of the present invention is that a cylinder having a cylinder bore into which a piston slides is rotatably supported within the outer shell of the fuselage, and an intake port and a discharge port are formed on the wall surface of the outer shell through which the cylinder bore and the cylinder circumferential surface alternately pass through as the cylinder rotates. the piston head, which opens the port and whose volume changes as the cylinder rotates;
The fluid is conveyed from the suction port to the discharge port by alternately communicating the working chamber surrounded by the inner wall of the bore and the inner periphery of the outer shell with the suction port and the discharge port. .

[Embodiments of the invention]

An embodiment of the present invention will be explained in detail with reference to FIGS. 1 to 3.

A shell 1 forming the outer shell of the fuselage has a cylindrical space surrounded by a cylindrical wall surface 1a.

Both ends of the shell 1 are side plates 2a and 2b.
The space within the shell 1 becomes a substantially closed space.

A cylindrical cylinder 3 inserted into the shell 1 has two orthogonal bores 4a, 4b.

Double-headed pistons 5a and 5b are inserted into the bores 4a and 4b, respectively.

Each head of the double-headed pistons 5a and 5b is connected to the cylinder 3.
It is cut into a curved shape that forms part of the outer peripheral surface of.

A hole 3a for inserting the shaft 7 is formed through the center of the cylinder 3, and annular protrusions 3b and 3c, to which inner rings of bearings 6a and 6b are fixed, are integrally formed around the hole 3a on both end faces of the cylinder 3. is formed.

The outer rings of the bearings 6a, 6b are annular projections 2c formed on the inner end surfaces of the side plates 2a, 2b.
It is fixed to the inner circumference of 2d.

Annular projections 2c, 2 of side plates 2a, 2b
The outer periphery of d is fitted into both ends of the cylindrical wall surface 1a of the shell 1, and seal rings 2g and 2h are provided at the portions where the annular protrusions 2c and 2d contact with the flange portions 2e and 2f of the side plates 2a and 2b. and attach the side plate 2 with four screws 2i and 2j each.
When screwed to the ears 1b and 1c of the shells a and 2b, a seal is created between the two.

A dashed line l indicates the central axis of the internal space of the shell 1 and the rotational axis of the cylindrical cylinder 3, and the rotational centers of the bearings 6a and 6b coincide with this axis l.

Another pair of bearings 8a, 8b are fixed inside the side plates 2a, 2b.

Bearings 8a, 8b are bearings 6a, 6b
and outside the cylinder 3.

The inner rings of the bearings 8a and 8b are press-fitted into the shaft 7 to receive rotation of the shaft 7.

The shaft 7 passes through the cylinder 3 in the axial direction, and its one end is supported by the inner ring of the bearing 8b, and the other end is supported by the inner ring of the bearing 8a. It protrudes from the outside of the aircraft.

9a and 9b indicate a fixed ring and a vibrator that constitute the shaft seal device.

Shaft 7 is the center of rotation of cylinder 3 (axis l)
2 and 3, the center of rotation (axis m and point P
).

5c to 5e are cylinders 3 for passing shaft 7.
A part of the through hole is shown.

A hole 5f through which the shaft 7 also passes through the pistons 5a and 5b slidably inserted into the bores 4a and 4b;
5g is formed.

Cams 7a and 7b are integrally formed on the shaft 7 at positions corresponding to the pistons 5a and 5b<the axial center position.

The cams 7a and 7b are formed so that the bulges are located at positions shifted by 180 degrees from each other.

Both of the cams 7a and 7b have their centers at positions offset by a dimension S from the center of rotation of the shaft 7.

Cams 7a and 7b are pistons 5a and 5b, respectively.
is rotatably inserted into the holes 5f and 5g.

The operating principle will be explained based on FIGS. 3 and 4.

In FIGS. 3 and 4, O indicates the center of rotation of the cylinder 3, P indicates the center of rotation of the shaft 7, and Q indicates the center point of the cam.

The cylinder 3 and the shaft 7 are supported by the shell through bearings 6a, 6b and 8a, 8b, respectively, so that their centers of rotation are fixed.

When the shaft 7 rotates in the direction of the arrow in FIGS. 3 and 4, the piston 5a receives a force directed to the right in the drawings by the cam 7.

This force rotates the piston 5a and cylinder 3 assembly in the same direction as the shaft 7 rotation direction.

As shown in FIG. 4b, when the shaft 7 rotates 90 degrees and the axis passing through the rotation center P of the shaft 7 and the center point Q of the cam forms a 90 degree angle with the base line Y, the cylinder 3 is rotated 45 degrees, cylinder bore 4
The central axis of a (the axis passing through points O and Q) forms an angle of 45 degrees with respect to the base line Y.

At this time, the piston 5a slides within the cylinder bore 4a along the central axis of the bore by 2-√2/4 strokes toward one side of the piston _5a2 of the double-headed piston 5a. This stroke is shorter than the eccentricity S of the cam 7a.

As a result, a working chamber 4a 2 is closed in the cylinder bore _4a by the head of the piston 5a ₂ and the shell 1.
The volume of the space decreases by an amount corresponding to 2-√2/4 strokes of the piston 5a, and the fluid inside the space is compressed.

At this time, conversely, between the head of the piston 5a ₁ and the shell 1, a working chamber 4a ₁ is formed with a volume corresponding to 2-√2/4 strokes of the piston 5a. At the same time, the suction port 10, which had been closed by the peripheral wall of the cylinder 3, opens into the working chamber _4a1 , and fluid is sucked into the working chamber _4a1 through the suction port 1d and the passage 1e.

As shown in FIG. 4c, when the shaft 7 rotates 180 degrees and the center Q of the cam 7a comes to a position where it overlaps the center of rotation of the cylinder 3, the cylinder 3 rotates 90 degrees and the piston 5a moves inside the bore 4a. Room 4a To _{the 2} side Figure 4a
Displaced by 1/2 stroke from the position. As a result, the fluid in the working chamber _4a2 is compressed to 1/2 the volume, while (2+√2) times as much fluid as b is sucked into the working chamber _4a1 .

At this time, the working chamber _4a2 communicates with the discharge port 11 provided in the shell 1, and the compressed fluid flows through the discharge port 11.
1 through the discharge valve mechanism 1g shown in FIG. 3, and reaches the discharge port 1i through the passage 1h.

When the shaft 7 further rotates 90 degrees and the cylinder ₃ rotates to the position shown in _FIG . increase.

In this way, the shaft 7 has rotated 360 degrees as shown in Fig. 4e.
In this state, the suction port 10 is closed by the cylinder circumference.
and the discharge port 11 are closed.

As a result, this position becomes the maximum volume position of the working chamber _4a1 . At this time, the piston strokes by a distance of 2S every time the cylinder rotates 90 degrees, so in the state e where the cylinder rotates 180 degrees, the piston strokes by 4S.

As the shaft 7 continues to rotate further, the volume of the working chamber 4a ₁ decreases, and the volume of the working chamber 4a ₂ increases, and when the shaft rotates 360 degrees, it returns to the state shown in Figure 4a, and now each working chamber 4a ₁ , 4a ₂ completes one step of suction and compression.

Therefore, when the shaft 7 rotates twice, the cylinder 3
rotates once, and the piston 5a reciprocates within the bore 4 once.

After all, in this crank mechanism, the cylinder rotates at an angular velocity of 1/2 of the rotation of the shaft, and the piston reciprocates.

As a result, if the shaft is rotated at twice the rotation speed of a conventional fluid machine shaft, the drive torque required to rotate the shaft (or the amount of work required per shaft rotation) is halved, and the shaft can be rotated by half. A high-speed type prime mover can be used as the prime mover for this purpose, and in the end, a small size prime mover can be used.

For example, when applied to a compressor that makes up the refrigeration cycle of a vehicle air conditioner, a V-belt and pulley are used to transmit the rotational force of the engine to the compressor. In order to do so, it is necessary to increase the pulley ratio. This means that the pulley on the compressor side can be made smaller in diameter.
This means that it is possible to downsize the rotational force transmission mechanism.

Furthermore, an electromagnetic clutch is provided at the input end of the compressor shaft, and the electromagnetic clutch is configured to be able to transmit and interrupt the transmission of the rotational force of the engine.
The fact that the driving torque of the compressor can be reduced as described above means that the shearing torque acting on the friction surface of the clutch is also small, and the electromagnetic attraction force of the clutch can also be small. As a result, the electromagnet device and friction plate that generate the electromagnetic attraction force can be made smaller. Since the above-mentioned pulley is formed in this electromagnetic clutch, the pulley can be made smaller in diameter, the electromagnet device and the friction plate can be made smaller, and the transmission mechanism, that is, the electromagnetic clutch can be made smaller.

Here, in this embodiment, the discharge port and the working chamber are configured so that they do not communicate with each other until the cylinder is rotated nearly 90 degrees from the position where the working chamber reaches its maximum volume position, but this compresses the fluid at a predetermined compression ratio. Therefore, the communication start position between the discharge port and the working chamber can be freely selected depending on the compression ratio.

The communication start position between the port and the working chamber can be freely selected depending on the non-compression ratio.

When transporting incompressible fluid, follow the dashed line 1 in Figure 4a.
As shown by 1', the discharge port can be configured to communicate with the working chamber immediately after the maximum volume position of the working chamber.

In addition, the amount of displacement of the piston is four times the amount of eccentricity S of the cams 7a and 7b, and in the crank mechanism of a fluid machine equipped with conventional reciprocating pistons, the amount of displacement of the piston is Since the amount of eccentricity is twice that of the cam (corresponding to the example cam), twice the displacement of the conventional cam can be obtained.

4A to 4E show the operation of the piston 5b, in which the piston 5b is advanced by 90 degrees relative to the piston 5a in terms of cylinder rotation angle.

Therefore, Figure 4A corresponds to Figure 4C, and B corresponds to d to C.
correspond to e, respectively, and D and E are in a state where the rotation angle of the cylinder has advanced by 45 degrees and 90 degrees, respectively, from the state of e.

The suction compression action is exactly the same as that described in FIGS. 4a to 4e.

An improved embodiment is shown in FIGS. 5 to 7.

In the improved embodiment, the cams 7a, 7b connect to the piston 5 via needle bearings 13a, 13b.
It is fitted into the holes 5f and 5g of a and 5b.

This reduces friction loss between the cam and the hole, resulting in smooth rotation. Furthermore, the generation of frictional heat can be reduced, and a small amount of lubricating oil is sufficient.

In the improved embodiment, the discharge valve mechanism 1g is eliminated. This is because the circumferential surface of the cylinder itself has the function of closing the port until the cylinder bore rotates to the position of the discharge port, acting as if it were a discharge valve. The compression ratio is arbitrarily determined by the opening position of the discharge port and the diameter of the port.

Furthermore, in this embodiment, the outer diameter of the fuselage body is made as small as possible without reducing the strength of the shaft.

The shaft 7 and cam 7a of the embodiment shown in FIG.
As shown in FIG. 8 _, the diameter of the cams 7a and 7b is φd _{p as shown in FIG. 8, where φd s is} the shaft diameter and _S is the eccentricity between the shaft and the cam.

In order to secure the piston stroke (4 times S) while maintaining the strength of the shaft, the cam diameter _dp has to be quite large.

By the way, if the diameters of the cam insertion holes 5f and 5g of the piston can be made smaller, the axial length of the piston can be reduced accordingly.

In addition, as shown in FIGS. 2 and 6, the cylinder bore 4
a, 4b, the end face of the shaft insertion hole 5c of the cylinder 3 is the bottom dead center. Therefore, if the shaft insertion hole 5c can be made smaller, the outer diameter of the machine body can be made smaller by that amount when the piston stroke is the same.

Therefore, the cam diameter is made smaller without changing the amount of eccentricity so that the opposite side of the cams 7a and 7b is closer to the center of the shaft than the outer diameter of the shaft 7, and reliefs 7c to 7e for piston assembly are provided. It is formed around the shaft circumference around the cam on the opposite side from the cam bulge.
The installation of the shaft will be explained based on FIG. 9. In the embodiment, bearings 13a and 13b are installed by utilizing the reduced diameter of the cam insertion hole of the piston.
are press-fitted into holes 5f and 5g. After all, the inner diameter of the bearing is equal to the outer diameter of the cams 7a, 7b.

In Fig. 9, the shaft 7 is fixed and the piston 5 is
a and 5b are bores 4a and 4b of cylinder 3, respectively
However, the cylinder is not shown in FIG.

Shaft 7 is inserted into shaft insertion hole 5c of cylinder 3.
Insert the side end of the cam 7b and send the cylinder 3 to the left in the drawing.

As shown in FIG. 9a, when the piston 5a comes to the position corresponding to the relief 7d, the bearing 13a moves to the relief 7.
Move the cylinder 3 so that it comes into contact with d. In this state, if the cylinder 3 is sent to the left in the drawing as shown in FIG. 9b, the piston 5a passes through the cam 7b and moves to a position corresponding to the relief 7c.

Next, by rotating the piston 5a clockwise and moving the cylinder 3 further to the left, the piston 5a moves to the position corresponding to the relief 7e, and the piston 5b moves to the position corresponding to the relief 7d, as shown in FIG. 9d. do.

Here, as shown in FIG. 9e, the cylinder 3 is moved upward to bring the bearing 13a into contact with the relief 7e, and the piston 5b is pushed down to bring the bearing 13b into contact with the relief 7d.

If the cylinder 3 is sent to the left in this state, the two pistons 5a and 5b are attached to the cams 7a and 7b as shown in FIG. 9f.

In this way, while the shaft is fixed and the cylinder is sent in one direction, the cylinder and piston can be moved up and down.
And the shaft can be installed just by rotating it.
Automation of assembly will also become possible.

Here, to explain the case where there are no reliefs 7c to 7d using FIG. 9a, if the cylinder is lifted up and down by the dimension t of the relief 7d in FIG. This means that the cylinder will not be able to be sent to the left as it will collide with the cylinder. Providing this relief is absolutely necessary in order to reduce the diameter of the cam insertion hole of the piston.

Thus, in this embodiment, a bearing could be interposed between the cam and the piston despite having the same outer diameter as that of the embodiment shown in FIGS. 1 to 3.

Furthermore, since the outer diameter of the cam can be made smaller, the cam insertion hole 5c can be made smaller than that of the first embodiment, and the bottom dead center of the bore can be moved closer to the center. Therefore, by shortening the axial length of the piston by that amount without intervening a bearing, the outer diameter of the body can be reduced.

Further, in the second embodiment, the suction passage is branched into two passages 1e ₁ and 1e ₂ , and each passage communicates with the suction port 10a that opens immediately after the suction stroke and the working chamber at an intermediate position of the suction stroke. port 10b
is connected to.

A passage opening/closing valve 12 is installed in the middle of the passage _1e2 communicating with the port 10b.

This configuration is similarly configured for the suction passage communicating with the cylinder bore 4b.

The capacity of the fluid machine can be controlled by switching and controlling the flow path opening/closing valve 12.

The operation will be explained below based on FIGS. 10 and 11.

FIG. 10 shows the operation when the passage opening/closing valve 12 opens the passage _1e2 .

When _the cylinder 3 starts to rotate clockwise from the state shown in FIG _. The suction port 10a communicates with the working chamber ₄₃₁ , and the suction process in the working chamber _4a1 starts.

FIG. 10b shows the cylinder 3 rotated by 45 degrees.

When the cylinder 3 rotates 90 degrees from the state shown in FIG. 10a, the suction port 10b communicates with the working chamber _4a1 as shown in FIG. 10c. As a result, in this state, fluid is sucked from both ports 10a and 10b.

When the cylinder 3 further rotates, the suction port 10a is closed on the circumferential surface of the cylinder 3, as shown in FIG. 10d, and fluid is sucked into the working chamber _4a1 only from the port 10b.

When the cylinder rotates 180 degrees, the suction port 10a,
10b are both closed by the circumferential surface of the cylinder 3,
The suction process in the working chamber _4a1 is completed.

Thus, when the flow path opening/closing valve 12 is open, fluid is sucked into the working chamber from either the suction port 10a, both suction ports 10a and 10b, or the suction port 10b while the working chamber is in the suction process. It turns out.

Next, the operation of the machine when the flow path opening/closing valve 12 is closed to reduce the capacity will be explained based on FIG. 11.

As shown in FIG. 10, the rotation of the cylinder 3 causes the working chamber _4a1 and the suction port 10a to communicate with each other immediately after the start of the suction stroke, and fluid suction begins.

However, when the cylinder rotates 90 degrees and the suction port 10b comes to a position facing the working chamber as shown in FIG. 11c, no fluid is sucked from the suction port 10b because the passage _1e2 is closed.

Not only that, but the cylinder rotates further and the 11th
As shown in Figure d, the cylinder peripheral surface is the suction port 10a.
When the valve is closed, fluid is no longer sucked into the working chamber _4a1 .

When the cylinder 3 continues to rotate in this state, the confined fluid expands in the working chamber _4a1 whose volume increases.

After passing the state shown in FIG. 11e, the working chamber _4a1 enters the compression process, but since the fluid has expanded in advance, the fluid is not substantially compressed until the expansion is exhausted.

Therefore, during this period, the machine essentially does no work and is in a lossless state.

This is because there is no wasted work that occurs in the case of conventional capacity control that restricts the suction passage.
This has the effect of not causing loss of driving energy.

In this way, when the flow path opening/closing valve 12 is closed, only the fluid sucked while the suction port 10a communicates with the working chamber _4a1 is compressed and discharged, and the volume of the discharged fluid is reduced. Capacity control is achieved.

In addition, when this fluid machine is applied as a compressor constituting the refrigeration cycle of the above-mentioned automobile air conditioner, the flow path opening/closing valve is composed of a solenoid valve, and the solenoid valve is operated according to the heat load to control the capacity. Or, when the engine speed exceeds a predetermined value, a solenoid valve is activated to close the passage and control the capacity.

In this embodiment, a four-cylinder type fluid machine has been described, but it is also possible to increase or decrease the number of double-ended pistons to create a two-cylinder or six-cylinder fluid machine.

〔Effect of the invention〕

As explained above, according to the present invention, there is a cylinder that rotates within the shell, a bore formed within the cylinder, a piston that slides into the bore, and a rotation that causes the piston to reciprocate within the bore while rotating the cylinder within the shell. A driving mechanism is provided, and the volume of the working chamber surrounded by the head of the piston, the inner wall of the shell, and the wall of the bore is configured to increase and decrease repeatedly as the cylinder rotates. The suction port provided in the shell communicates with the working chamber to suck fluid into the working chamber, and then, while the volume of the working chamber is decreasing, the discharge port provided in the shell communicates with the working chamber to draw fluid in the working chamber from the discharge port. Since the fluid is configured to discharge fluid from the suction port to the discharge port, the crank mechanism that reciprocates the piston can be constructed extremely compactly with a small number of parts, creating a fluid machine with a small volume occupied by the crank mechanism. can be obtained.

Further, according to the present invention, by arbitrarily selecting the position of the discharge port, it is possible to arbitrarily adjust the compression ratio of the fluid.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an embodiment of the fluid machine according to the present invention, FIG. 2 is a cross-sectional view of the same, FIG. 3 is a cross-sectional view of FIG. 2, and FIGS. E is a drawing for explaining the operating principle of the fluid machine according to the present invention, FIG. 5 is an exploded perspective view of another embodiment, FIG. 6 is a cross-sectional view of the same, and FIG. 7 is a - cross section of FIG. 6. figure,
FIG. 8 is a diagram showing the shape of the shaft and cam of the first embodiment, FIGS. 9 a to f are diagrams for explaining the shaft assembly process of the second embodiment, and FIGS. 10 a to
e and FIGS. 11a to 11e are drawings for explaining the operation of the capacity control mechanism of the second embodiment. 1...Ciel, 3...Cylinder, 4a, 4b...
...Bore, 5a, 5b...Double-ended piston, 7...Shaft, 7a, 7b...Cam, 10...Suction port, 11...Discharge port.

Claims (1)

[Scope of Claims] 1. A shell that forms the outer shell of the fuselage and has a substantially closed cylindrical space surrounded by a cylindrical wall inside, which is inserted into the cylindrical space within the shell,
and a cylindrical cylinder rotatably supported by the shell, which is inserted into a shaft hole extending through the cylinder in the axial direction, and has its rotation center at a position offset by a predetermined amount with respect to the rotation center of the cylinder. a rotating shaft supported by the shell; a pair of cylinder bores extending through the cylinder such that the center axes thereof are perpendicular to each other with a predetermined distance therebetween; a double-headed piston that slides within each cylinder bore; a cam hole that extends through each piston and has a center equidistant from both heads;
It is fixed to the shaft and rotatably inserted into the cam hole, has a center at a position eccentric by a distance equal to the eccentricity between the rotation center of the cylinder and the rotation center of the shaft, and has a center in the eccentric direction. a pair of disk-shaped cams configured such that the cams are 180° shifted from each other in opposite directions; the shell introduces fluid into a working chamber surrounded by each head of each piston, a cylindrical wall surface of the shell, and a cylinder bore; A fluid machine having a suction port provided in the shell, and a discharge port provided in the shell for leading out fluid from the working chamber. 2. In the device described in claim 1, a portion of the circumferential side portions of both cylinder bores overlap each other at the center of the cylinder bore in the piston sliding direction, and a portion of the shaft hole is formed there. A fluid machine characterized by: 3. The fluid machine according to claim 1, wherein the cylinder is supported at both ends by bearings fixed to the shell. 4. The fluid machine according to claim 1, wherein the rotating shaft is supported at both ends by bearings having outer rings fixed to the shell. 5. In the item set forth in claim 1, a first shell fixed to the shell at both ends of the cylindrical space and centered with respect to the central axis of the cylindrical space.
a second bearing member fixed to the shell, the second bearing member having an axis offset from the axis of the first bearing member by a predetermined amount, the cylinder attached to the first bearing member; A fluid machine characterized in that each of the rotating shafts is supported by a second bearing member.