JPH0494423A - Rotary engine - Google Patents

Abstract

PURPOSE:To reduce the transmission loss by fitting two pairs of deformed gears to a shaft with the same center and another shaft, fitting rotors with rotor heads to the same shaft respectively, and combining them with a housing having an intake port, an exhaust port and an ignition plug. CONSTITUTION:When ignition explosion is generated by an ignition plug 17, rotor heads 10, 12 are applied with the equivalent forces in opposite directions and transfer them to gears 5, 6 via shafts 1, 2. The distance between the shaft 1 and an action point A where gears 5, 7 am engaged is shorter than the distance between the shaft 2 and an action point B where gears 6, 8 are engaged, thus a larger force is generated at the action point A by the function of the moment of force. During this explosion stroke, rotor heads 11, 13 intake the air-fuel mixture from an intake port, the air-fuel mixture sucked in the previous stroke is compressed, and the burnt gas generated in the previous stroke is discharged from an exhaust port.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application This invention relates to a rotary engine that converts force by the difference in moment of force between two sets of deformable gears connected to two rotors.

(0) Conventional technology Until now, in a Wankel engine, a rice ball-shaped rotor attached to an eccentric shaft rotated while contacting a housing whose shape was a locus called a trochoid, resulting in an intake compression ignition explosion exhaust cycle. It had a repeating structure.

In this Wankel engine, the rotor is attached to an eccentric shaft, so a weight is required for balance, and the apex of the roughly triangular rotor, whose locus is called the internal line of the veritrochoid, is connected to the housing. Since there was line contact, multiple gas seals could not be applied. Due to this problem of maintaining airtightness and the unique shape of the rotor and housing, it is difficult to achieve a compression ratio high enough to cause an explosion by injecting fuel in a diesel-style manner.

Furthermore, the shape of the rotor and housing cannot be said to be easy to manufacture.

In an annular cylinder type rotary engine, rotation was obtained by rocking a plate attached diagonally to the output shaft due to the reciprocating motion of multiple cylinders.In order to smooth out zero rotation, many annular cylinders, which were difficult to manufacture, were arranged. There is. Along with this, the number of parts such as spark plugs increased, and the number of exhaust holes also increased.

Furthermore, since the locus of movement of the piston is not included in the rotational surface of the output shaft, there are also problems in terms of the mechanism and efficiency for obtaining rotational output.

Up until now, fluid compressors and fluid pumps have been of the piston type, impeller type, roots type, vane type, etc., but each has problems with vibration and the inability to freely change the rotation speed. However, in all formulas using rotors, there was a problem with airtightness because the rotors were in line contact with each other.

(c) Problems to be solved by the invention The problems to be solved by this invention are to have a structure that does not have any elements that require balance, is easy to maintain airtightness, can obtain the necessary compression ratio, and is The problem is what measures should be taken to create a simple rotary engine with a simple output conversion mechanism, a small number of parts, and an easy-to-manufacture shape.

(d) Means for Solving the Problems In order to solve the problems mentioned above, the rotary engine according to the present invention is as follows. That is, rotors (3), (4) and gears (5), (6) are attached to a shaft (1) and a shaft (2) passing therethrough, respectively.

Gears (5) and (6) are gears (7) attached to shaft (9)
, (8), each gear is a deformed tome-shaped gear with an apex every 180 degrees, and the diameter gradually decreases from the apex, and the gears mesh with each other to rotate with a changing rotational speed ratio. iI
Wheels (7) and (8) are installed with their vertices shifted 90 degrees in the rotational direction.

The rotors (3) and (4) are discs with rotor heads (10), (11), (12) and (13) at both ends in the radial direction.The rotor head is a sector-shaped columnar body when the rotor is viewed in the axial direction. Then, the rotors (3) and (4) are brought into close contact with each other in a cylindrical housing (.

14) When placed in the housing, the donut-shaped airtight chamber formed by the inner wall of the housing and the rotor is further divided into four airtight chambers. The relative positions in the rotational direction of the rotor head and the apex of the gears attached to the shafts (1) and (2) are made equal. Since the rotor, rotor head, and housing are in surface contact with each other, it is possible to provide as many gas and oil seals as necessary. The rotor and rotor head can be provided with holes of any desired shape for purposes such as cooling, lubrication and weight reduction.

The housing is provided with one intake port (15), one W port (16), one spark plug (17), or one fuel injector.

The intake and exhaust ports are located next to each other in the rotational direction, and the spark plug or fuel injector is located on the opposite side of the intake port in the radial direction, and there is no need for an intake valve or an exhaust valve.

In addition, as shown in the example introduced later, the gear is 90 mm.
It uses a tomoe-shaped rotor with an apex at each degree, and also uses a rotor with a rotor head at every 90 degrees, and is combined with a housing in which two sets of intake ports, exhaust ports, spark plugs, or fuel injectors are provided at 180 degree intervals. For example, this would be a rotor engine in which each suction, compression, explosion and exhaust stroke is carried out simultaneously on both radial sides.

Gears (7) and (8) are mounted with the tops of the gears at an angle of 45 degrees in the direction of rotation. By expanding this further, it is possible to create a rotary engine having two or more times the number of gear vertices and rotor heads.

In addition, the shape of the gear is not limited to the tomoe shape, but as shown in the examples introduced later, there are also those whose diameter decreases stepwise, those with a combination of large and small fan shapes, and the number of vertices of the mating gear. Various shapes and sizes can be designed, such as those with half the number of teeth and combinations. Regarding the shape of the rotor, it is also possible to cut out the housing portion and integrate it into the rotor. If cooling fins are provided on the externally exposed portion of the rotor, this itself forms a rotating cooler. Also, if a large number of radial blades are attached instead of cooling fins and covered, this will constitute an integrated supercharger. Conversely, if you place the blades so that they hit the exhaust gas coming out of the exhaust port, this becomes an integrated exhaust turbine. Any combination of up to three of these can be used.

When a turbocharger is installed, or even without it, if the intake and exhaust ports are installed so that they partially overlap in the circumferential direction, as shown in the example introduced later, the effect of expelling burned gas with intake air can be achieved. can be done.

Since the rotor can be structured to be exposed to the outside, gears (5) and (6) can be attached to the shaft (
It can be attached directly to the rotors (3) and (4) without going through 1) and (2). Also at this time, gear (7), (
As for 8), if the number of vertices and the number of teeth of the gear attached to the rotor are half, the overall device does not need to be large.

As for shafts (1) and (2>), as will be shown in the action explained later, the rotor heads swing relative to each other between the rotor heads of the other rotor, and do not overtake them. Therefore, instead of making the shaft pass through the inside of the shaft, it is possible to create two pairs of shafts, or multiple pairs of shafts, both of which are shaped like vertically split bamboo into about one-eighth pieces and placed on the same circumference. .

By combining this and the two structural characteristics of being able to expose the rotor to the outside, as shown in the example introduced later, we have created a shaft (1) in which the rotors are placed directly or on the same circumference. , (2), it is possible to connect a plurality of rotary engines according to the present invention without going through other shafts or gears. The shapes of the rotor, housing, gear and shaft can be designed in various ways.

At this time, if a part of the plurality of connected units is a fluid compressor or a fluid pump, this becomes a prime mover-integrated rotary fluid compressor or fluid pump.

When a motor-integrated rotary fluid compressor or fluid pump is used, the number of vertices of the rotor head and gears may be an odd number of 3 or more, as shown in an embodiment to be introduced later.

Furthermore, it is of course possible to use a rotary fluid compressor or a fluid pump using external power.

In this case, the number of vertices of the rotor head and gear is 1 each.
It also performs a specific function as an individual.

Of course, it is possible to use the external combustion engine to obtain rotational power by taking in steam or the like from the outside, or to operate an integrated rotary fluid compressor or fluid pump.

The rotary engine according to the present invention can be freely designed in many shapes and combinations in addition to the shapes and combinations shown in the embodiments to be introduced later.

(f) Operation The rotary engine according to the present invention operates as follows. Now rotor head (10) and rotor (4) of rotor (3)
The rotor head (12) of the spark plug is closest to the spark plug with the gasoline mixture compressed. The rotor head (10) is located at the head in the traveling direction. On the opposite side in the radial direction, the rotor heads (11) and (13) are also closest to each other, but this is where exhaustion ends and intake is about to begin.

At this time, the valley portion of the gear (5) and the apex of the gear (7) mesh with each other, and the teeth at a position 90 degrees from the apex of the gear (8) mesh with the corresponding teeth of the gear (6). When an ignition explosion occurs due to the spark plug (17), the rotor heads (10) and (12) receive equal forces in opposite directions. This force is transmitted through the shafts (1) and (2) to the gear (5).
), (6).

If the meshing point of gear (5) and gear (7) is point of action A, and that of gear (6) and gear (8) is point of action B, then the distance of point A from axis (1) is the point of action. Since it is shorter than that of B, a larger force is generated at the point of application A due to the action of the moment of force. In other words, the force with which gear (5) turns gear (7) is greater than the force with which gear (6) tries to turn gear (8) in the opposite direction, so gear (7) is fixedly attached to shaft (9). , (8) eventually rotate in the direction in which gear (5) turns gear (7). Then, gear (6) will also rotate in the same direction as gear (5), but as mentioned earlier, the distance from the axis (1) of the point of action A is shorter than that of the point of action B, so the diameter Since it is smaller, the rotation angle of gear (5) is larger than that of gear (6).

Therefore, the rotor (3) connected to the gear (5) through the shaft (1) rotates at a higher rotational speed than the rotor (4) connected through the gear (6) and the shaft (2), and the rotor The heads (10) and (12) rotate in the same direction while gradually expanding the working chamber between them, and the rotor head (12) rotates in the same direction while gradually expanding the working chamber between them.
10) catches up with the rotor head (13), this explosion stroke ends.

At exactly the same time that this explosion stroke is being carried out, the rotor heads (11) and (13) expand the working chamber between them, so the air-fuel mixture is sucked in from the intake port, and the rotor head (11)
Contrary to (12), the working chamber is narrowed to compress the air-fuel mixture sucked in in the previous stroke. The rotor heads (10) and (13) similarly narrow the working chamber and discharge the burned gas generated in the previous stroke from the exhaust port.

That is, in the rotary engine according to the present invention, four strokes of suction, compression, explosion and exhaust are performed simultaneously. and rotor head (
When 11) comes closest to (12), this time gear (6)
The valley part of the gear (8) meshes with the top of the gear (7).
) meshes with the corresponding tooth of gear (5), that is, the beginning of the previous stroke occurs again with rotors (3) and (4) swapped. Moreover, since the gears (7) and (8) are mounted 90 degrees apart in the rotational direction, everything occurs in exactly the same position as in the previous stroke. Therefore, only one intake port, one exhaust port, one spark plaque, or one fuel injector is required.

In this way, the rotor heads rotate one after another while catching up with and being overtaken by the rotor head of the other rotor, transmitting the rotation to the shaft [9] through two sets of gears, and extracting power from the shaft (1) or (2). ) It is also possible to extract power directly from the

If the compression ratio is increased by increasing the circumferential length of the rotor head within the range allowed by the shape of the deformed gear, it is possible to create a system in which only air is sucked in and compressed, and fuel is injected into it to cause an explosion. can.

When the shaft (9) is used as the output shaft, one explosion occurs every quarter rotation of the output shaft, so the rotation is smooth. If the number of vertices of the rotor head and gears is increased by multiples of 2, the explosion will be more precise and will occur at multiple locations simultaneously, resulting in extremely smooth rotation.

When used solely as a rotary fluid compressor or pump, the rotation of shaft (9) or shaft (1) or (2) can be reversibly converted into compressive force using exactly the same principle as above.

(f) Example Example 1 FIG. 1 is an exploded perspective view showing a first embodiment.

In Example 1, the rotors (3) and (4) have rotor heads (10), (11), and (12) at both ends in the radial direction.
, (13), the gear has a vertex every 180 degrees, and the diameter gradually decreases from the vertex (5), (6), (7), (8)
, and attach them to the shaft (1), the shaft (2) passing through it, and the other shaft (9).

The housing (14) has a cylindrical shape with lids on both bottoms and completely encloses the rotors (3) and (4). Intake port (15
), and the exhaust ports (16) are located at 311 locations on the lid and the cylindrical portion of both bottoms of the housing so that intake and exhaust can be easily carried out. I installed a spark plug (17) to make it a gasoline mixture intake system. The movements of the rotor and gears in Example 1 are sequentially shown in FIGS. 2, 3, and 4. The movements of the rotor and gears are basically the same in all other embodiments.

In addition, when all the gears are tomoe-shaped and have the same shape, the maximum value of the central angle of one rotor head is determined as follows. In other words, a length equal to the length of the circumference from the top of the gear to a point turned 90 degrees from the valley side is taken, and the central angle from that point to the top is the central angle of the rotor head.

Example 2 FIG. 5 is a front view showing the main parts of the second embodiment.

It has the same configuration as Example 1, except that in Example 2, the intake port (15) on the upper lid side is slightly pushed toward the exhaust port (16) side, and the remaining burned gas is expelled to the exhaust port on the lower lid side. I can do it.

Example 3 FIG. 6 is a perspective view showing the main parts of the third embodiment.

In Example 3, a housing having the same configuration as Example 1 was used, with the cylindrical portion bulging outward. The rotor head also has a rounded outer circumference. Here, the rotor is disk-shaped. This has the advantage that there are fewer places where the gas seal oil seal bends at right angles.

Embodiment 4 FIG. 7 is an exploded perspective view showing essential parts of Embodiment 4. An example is shown in which the hole (18) of the required shape can be made in the rotor and rotor head using the same configuration as in Example 1.

In Example 4, the inlet (
19), and pass through the inside of the rotor and rotor head and install a hole (18) with a discharge port (20) on the side of the rotor that is far from the axis.
) was opened and the coolant was passed through. Lubricating oil may be used as the coolant. Two concentric grooves (21) are made on the housing side where the inlet and outlet rotate, and pipes (22) are used to take in and discharge the coolant from the outside. ) has the advantage that the rotor and rotor head can be cooled from inside.

Example 5 FIG. 8 is a plan view showing the main parts of the fifth embodiment.

In Example 5, a combination of large and small sector shapes was used as the gear. When replacing the gear used in Example 1, the center angle of the fan shape with the larger diameter of gears (5) and (6) should be made equal to the center angle of the rotor head, and the gear (7) should be replaced with the gear used in Example 1.
, (8), the central angles of the large and small sectors are each 90 degrees. Then, they are attached to the shaft (9) with a rotational direction shifted by 90 degrees. Also, the length of each diameter can be freely set within the range that satisfies the conditions that the number of teeth that engage with each other is equal and the distance between the shafts is constant.

Example 6 FIG. 9 is a plan view showing the main parts of the sixth embodiment.

In the sixth embodiment, the gear can be freely designed within a range that satisfies the condition that the distance between the axes whose diameter decreases stepwise becomes constant. Note that the relationship with the maximum value of the center angle of the rotor head is the same as described at the end of the first embodiment.

Example 7 FIG. 10 is an exploded plan view showing the seventh embodiment.

In Example 7, the gear is shaped like a tomoe with apexes at every 90 degrees, a rotor with a rotor head at every <90 degrees is used, and the intake port, exhaust port, spark plug, or fuel injector is connected to two It is combined with housings provided every 180 degrees. Gear (7).

(8) is attached to the shaft (9) with a 45 degree shift in the direction of rotation. Each stroke of suction, compression, explosion and exhaust is performed simultaneously on both sides in the radial direction, and if the shaft (9) is used as the output shaft, a force is generated every 45 degrees of rotation of the output shaft, so the rotation becomes very smooth.

Embodiment 8 FIG. 11 is an exploded perspective view showing essential parts of Embodiment 8. In Example 8, the lids at both bottoms of the housing were cut out and integrated with the rotor, and cooling fins ( 23) was established. The cooling fins rotate as the rotor rotates, which is convenient for cooling. Here, cooling fins are also provided at the end of the rotor to blow air into the cylindrical housing, so both the rotor and the housing can be cooled together.

Example 9 FIG. 12 is a perspective view showing the main parts of the ninth embodiment.

In Example 9, holes (18) were drilled for cooling and weight reduction in the structure shown in Example 1, with the lids at both bottoms of the housing cut off and integrated with the rotor. It is.

Example 10 FIG. 13 is an assembled perspective view showing the 10th embodiment.

In Example 10, the gears (5) and (6) were directly attached to the rotor shown in Example 9. and gear (7),
Since (8) does not require the number of vertices and teeth of gears (5) and (6), the number of parts and manufacturing man-hours can be reduced.

It is also sturdy because it does not involve the shafts (1) and (2).

Example 11 FIG. 14 is an exploded perspective view showing the main parts of the 11th embodiment.

In Embodiment 11, two sets of rotary engines according to the present invention are connected, with the rotors connected to each other without a shaft and housed in one housing. In other words, two sets of rotors having the configuration shown in Example 1 are used, without using a shaft, a small circle II (24) is used to connect adjacent rotors, and a large disk is used to separate the rotor heads of rotors that are separated from each other. (25
) are used to connect each other and put them into one large cylindrical housing with lids on both bottoms.

A hole is made in the large partition disc to pass the small disc for connection. In order to balance the inertial mass of the rotor in the set with the large partition disc, the thickness of the rotor in the other set was increased. Here, two intake ports, two exhaust ports, and two spark plaques were attached to the cylindrical part of the housing.

Since the rotors are connected to each other without using shafts or gears,
When a plurality of rotary engines according to the present invention are connected together, there is an advantage that the whole can be made very compact and sturdy.

Example 12 FIG. 15 is an exploded perspective view showing the main parts of the twelfth embodiment.

In Example 12, the cylindrical portion of the housing shown in Example 11 was cut out and attached to the rotor in which the rotor heads were connected by a large partition disc to form a part of the rotor. Therefore, the upper and lower lids of the cylinder serve as a housing, and the intake port, exhaust port, and spark plug are located here.Since the inertial mass of the rotor, which is integrated with the cylinder, is greater, the shaft connected to this is used as the output shaft. .

Example 13 FIG. 16 is an exploded perspective view showing the main parts of the 13th embodiment.

In Embodiment 13, two sets of rotary engines according to the present invention are connected, and two sets of rotor heads are installed on the inside and outside of one cylinder and housed in one housing. A rotor with two rotor heads with the same central angle attached on both sides in the radial direction on concentric circles on one side plane of a large circle, and a partitioning cylinder attached to the rotor head with the same size and position as those rotor heads. (26) and a rotor with a small cylinder attached were combined with a housing consisting of an upper lid and a cylinder. Here, since it is easier to take up a larger area on the outside, the four outer working chambers are used as two sets of blowers, and the four inner working chambers are used as a rotary engine that performs a cycle of suction, compression, explosion, and exhaust.

In other words, there is no spark plug in the outer working chamber housing, and there are two sets of inlet (27) and outlet (28) every 180 degrees.
) was established. Inner intake and exhaust ports on the side that obtains power,
The spark plug must be installed in the upper lid of the housing.

The power-integrated blower can be made compact.

Example 14 FIG. 17 is an exploded perspective view showing the main parts of the 14th embodiment.

In Example 14, two sets of rotary engines according to the present invention are connected using two pairs of shafts placed on the same circumference. That is, on both sides of the circumference, the air compressor was placed on the opposite side of the rotary engine, which is powered by gears, in order to move it away from the source.

By using a shaft and a shaft passing through it, it is not possible to connect in this simple manner without using other shafts or gears.

Since the power and the compressor can be separated, there is an advantage that the air in the compressor is not heated unnecessarily.

Example 15 FIG. 18 is an exploded plan view showing the 15th embodiment.

Two sets of rotors having the configuration shown were connected and housed in two housings having the same configuration as shown in Example 1, respectively. The center of each rotor and gear is hollowed out to the extent that the shafts can swing relative to each other. *The degree of splitting is actually based on the center angle of the rotor head. Here, one of the two sets of rotary engines is rotated twice every 180 degrees, excluding the spark plug.
The air compressor was provided with a pair of intake ports (27) and discharge ports (28). The number of heating points is three each, creating six working chambers.

Four of them were used to perform four strokes of suction, compression, explosion, and exhaust, and the remaining two were used to perform two strokes of suction and exhaust. Of course, these two strokes can be used as a compressor, but in this case, these two strokes are used as idle strokes, and air is simply passed in and out without applying any load to cool the rotor head by directly exposing it to the outside air. did.

When the shaft (9) is used as the output shaft, an output is generated every 1/6 rotation of the output shaft, and at the same time, there is an advantage that the rotor head can be directly exposed to the outside air and cooled without intermittent power supply.

Example 16 FIG. 19 is an exploded plan view showing the 16th embodiment.

In Example 16, a rotary air compressor using external power was used. The number of vertices of the rotor head and gears was set to one each, and the rotor was completely covered by a housing having one inlet and one outlet.

The case with the simplest structure is shown.

(g) Effects of the invention When the rotary engine according to this invention is used, the following effects are achieved. In other words, the rotor, which is even when viewed in the axial direction, is mounted on a shaft that is not eccentric, so there is no need for any balancing weights.The shape of the rotor, including the rotor head, and its movement trajectory are very simple, and the housing is also very simple. The simplest shape is just a cylinder and does not require an intake valve or an exhaust valve, so it is very easy to manufacture. Since the rotor, rotor head, and housing are in surface contact with each other, airtightness is high. This and the ability to freely adjust the length of the rotor head in the circumferential direction allows for a compression ratio so high that it can cause an explosion during fuel injection. easily obtained. This allows them to operate economically using relatively cheap fuel at present.

The number of component parts is also very small for an engine capable of achieving high compression, and since only certain strokes are performed at certain locations, the number of parts can be reduced.

The mechanism that converts explosive force into rotational force, or rotational force into compressive force, has a clean structure in which the rotating surface of the rotor matches that of the output shaft, and in this respect, there are fewer components.

Looking at its operation as a prime mover, the four strokes of suction, compression, explosion, and exhaust are performed simultaneously, and the rotation is extremely smooth because force is generated at least every quarter rotation of the output shaft.

Since the shape and thickness of the rotor and the length of the rotor head in the radial and circumferential directions can be freely adjusted in conjunction with the design of the deformable gear, it is easy to create an engine with characteristics that suit the purpose.

Moreover, the rotors can be directly connected to each other without using other shafts or gears, and it is also possible to integrate the internal combustion engine with a fluid compressor or fluid pump, making it possible to create a very compact multi-rotary engine with little transmission loss. be able to.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing Embodiment 1 of this invention, FIGS. 2, 3, and 4 are explanatory diagrams of the operation of this invention, respectively.
FIG. 5 is a front view showing the main parts of the second embodiment of the present invention, and FIG.
7 is an exploded perspective view showing the main parts of Embodiment 4 of the invention. FIG. 8 is a perspective view showing the main parts of Embodiment 5 of the invention. A plan view, FIG. 9 is a plan view showing the main parts of Embodiment 6 of this invention, FIG. 10 is an exploded plan view showing Embodiment 7 of this invention, and FIG. 11 is a main part of Embodiment 8 of this invention. FIG. 12 is an exploded perspective view showing essential parts of Embodiment 9 of the present invention, FIG. 13 is an assembled perspective view showing Embodiment 10 of this invention, and FIG. 14 is Embodiment 11 of this invention. FIG. 15 is an exploded perspective view showing the main parts of Embodiment 12 of the present invention. FIG. 16 is an exploded perspective view showing the main parts of Embodiment 13 of the invention. FIG. 17 18 is an exploded perspective view showing the main parts of Embodiment 14 of the present invention.
The figure is an exploded plan view showing a fifteenth embodiment of the invention, and FIG. 19 is an exploded plan view showing a sixteenth embodiment of the invention. A... Point of action where gears (5) and (7) mesh B...
・Application points (1) and (2) where gears (6) and (8) mesh
)...Shaft (3), (4)...Rotor (5), (6), (7), (8)...Deformed gear (9)...Shaft (10), (11) , (12), (13)...
Rotor head (14)...Housing (15)...Intake port (16)...Exhaust port (17)...Spark plug (18)...Hole (19)...Inlet port (20) )...Discharge port (21), (22), (23), (24), (25), (26), (27), (28), small disk partition for connecting concentric groove pipe cooling fins Cylindrical inlet and outlet for large disk partition

Claims (1)

[Claims] One or two sets of deformable gears (5), (6), (7), (8) are attached to the same shafts (1), (2) and another shaft (9) having the same center, A rotor (3) with rotor heads on shafts (1) and (2)
), (4), respectively, and combined with a housing (14) provided with an intake port (15), an exhaust port (16), and a spark plug (17) or a fuel injector. 2. Directly connect one of the two sets of deformed gears to the rotor (3)
, (4). 3. A rotary engine in which part or all of the rotary engine according to claim 1 or 2 is a fluid compressor or a fluid pump.