WO2024005650A1

WO2024005650A1 - A rotation machine

Info

Publication number: WO2024005650A1
Application number: PCT/NO2023/060003
Authority: WO
Inventors: Kjell Vading
Original assignee: Vading Holding As
Priority date: 2022-06-29
Filing date: 2023-06-27
Publication date: 2024-01-04
Also published as: NO20220741A1

Abstract

A rotation machine having a first shaft (15) and a rotor (1; 5, 6, 7). The rotor (1; 5, 6, 7) comprising a first unit (1) having a first rotation axis (A) and a second unit (5, 6, 7) having a second rotation axis (B) different from said first rotation axis (A). The first unit (1) and the second unit (5, 6, 7) are rotationally coupled via a synchronization transmission (31) with a 1:1 exchange of rotation speed. The synchronization transmission comprises an outer transmission ring (17) and an inner transmission wheel (18). The outer transmission ring (17) has polygonal inside surface with a multiple of sides and the transmission wheel (18) has a polygonal outer surface with the same number of sides as the transmission ring (17). The transmission ring (17) is attached to either the first unit (1) or the second unit (5, 6, 7,), and the transmission wheel is attached to the other one of the first unit (1) and the second unit (5, 6, 7,).

Description

A ROTATION MACHINE

Technical Field

[0001] The present invention relates to a rotation machine having a synchronizing transmission, and more precisely a 1 :1 exchange transmission that couples different rotating parts that are intended rotate at the same speed and in synchronicity.

Background Art

[0002] In some appliances two parts cannot be connected through a fixed connection. This may be due to the rotation axes not being constant, such as if the rotation axis or a first part revolves relative to the rotation axis of a second part.

[0003] The 1 :1 exchange transmission of the present invention may however also be used to ensure synchronous rotation in machines where the axes are set at a constant distance and position from one another, but the rotation is transferred through a third component, such as in the compressor described in WO 2020/159381 , where a hub is rotatable about an axis A that is offset from an axis B of a housing. The rotation is transferred from a first shaft rotating about the axis B to the axis A through a set of cylinders that are coupled to the first shaft and a set of pistons that are coupled to the hub. The hub may rotate about the axis A but is not bound in its rotation about axis A.

[0004] The compressor of WO 2020/159381 works fine when it is in the intended operational speed. However, it has proven difficult to ensure proper rotation when the compressor is started and stopped. As the hub has to be linked to the pistons through a piston arm that can rotate both with respect to the hub and the piston, the hub will lag behind the pistons until the speed is sufficiently high that the centrifugal forces acting on the pistons will pull them outwards and thereby pull the hub into proper synchronous rotation. The same problem arises when the compressor is to be stopped, but with the hub then being somewhat ahead of the set of cylinders. WO 2020/159381 is incorporated herein by reference.

[0005] The 1 :1 exchange transmission of the present invention may also be used to synchronize the rotating parts of other rotation machines, such as the one described in WO 2020/159382. A rotation machine of this type will be used as an example below when the invention is described in more detail. WO 2020/159382 is incorporated herein by reference.

[0006] The present invention has some similarities with the transmission described in WO 2020/159383. This prior art transmission, however, has different speeds of the inbound axis and the outbound axis.

[0007] Reference should also be made to WO 2018/044342, which shows a hypocycloid device where the inbound and outbound axes have different speeds.

[0008] GB2161124, EP0017098 and US2008287244 describe various known polygonal gears.

Summary of invention

[0009] The above problem of synchronizing rotating parts in a rotation machine is solved according to the invention by a rotation machine having a first shaft and a rotor, said rotor comprising a first unit having a first rotation axis and a second unit having a second rotation axis different from said first rotation axis; said first unit and said second unit being rotationally coupled via a synchronization transmission with a 1 :1 exchange of rotation speed, characterised in that said synchronizing transmission comprises an outer transmission ring and an inner transmission wheel, said outer transmission ring having polygonal inside surface with a multiple of sides and said transmission wheel having a polygonal outer surface with the same number of sides as the transmission ring; the transmission ring being attached to either said first unit or said second unit, and said transmission wheel being attached to the other one of said first unit and said second unit.

[0010] Advantageous embodiments of the invention are defined in the dependent claims.

Brief description of drawings

Figure 1 shows a rotation machine according to the invention in partially exploded view,

Figure 1a shows a cross-section through the rotation machine of figure 1 ,

Figure 2 shows a vane unit comprised within the machine of figure 1 , Figure 3, shows a further exploded view of the machine of figure 1 ,

Figure 4 shows a part of a follower comprised within the machine of figure 1 ,

Figure 5 shows a longitudinal section through the machine of figure 1 ,

Figure 6 shows a detail of a one synchronization transmission unit according to the invention,

Figure 7 shows a detail of another synchronization transmission unit according to the invention,

Figures 8 and 9 show a different embodiment of the transmission ring and transmission wheel,

Figure 10 shows a cross-section of the synchronization transmission integrated in a piston type rotation machine.

Detailed description of the invention

[0011] Figure 1 shows a partially exploded view of a rotation machine. The rotation machine is based on the principles of WO 2020/159382. It comprises a rotor in the form of a vane unit 1 . The vane unit (without the follower) is shown separately in figure 2, and comprises an outer ring 2, a number of vanes 3, which conveniently are three, and a central shaft 4. All of these parts are formed integral, so that the vane unit 1 without the follower is a single piece.

[0012] Inside of the outer ring 2 is a follower comprising three semi-circular segments 5, 6 and 7. These extend between the vanes 3 and form together a circle. This circle is not concentric with the outer ring 2 but has a centre axis that is offset from the axis of the shaft 4. The segments 5, 6 and 7 are also shown in the exploded view of figure 3.

[0013] The segments 5, 6, 7 are carried by small cylinders 8, which, as shown in figure 3 have a longitudinal slit 9 that extends from one end and almost divides the cylinder in two. The vanes 3 extend through the slits 9 in the cylinders 8. The cylinders 8 may slide inwards and outwards on the vanes 3, and the segments 5, 6, 7, which have a corresponding cylindrical face 30 resting against the cylinders 8, may slide circumferentially on the outer surface of the cylinders 8. [0014] The machine has an end cover 40, 11 at each side. The end covers 40, 11 are attached to an outer housing, which is not shown in the figures.

[0015] A support disc 10 has on its inside a race 12 (see figure 4), along which bearings 13 journaled at the end of the cylinders 8 may run.

[0016] The machine has a shaft 15 protruding from the second cover 11 . The coupling between this shaft 15 and the vane unit 1 will be explained below.

[0017] The machine has two synchronization transmission units 31 and 32, one at each end of the vane unit 1. The two units 31 , 32 are in principle similar and they will be explained in detail by referring to figure 7, which shows the first transmission unit 31.

[0018] Figure 1 a shows a cross-section through the rotation machine of figure 1 , showing the housing 44, the vane unit 1 with the outer ring 2 and vanes 3. The central shaft 4 of the vane unit 1 has an axis A. Also shown are the segments 5, 5 and 7 of the follower. The segments have a rotation axis B that is offset a distance d from the rotation axis A of the vane unit 1 .

[0019] The cylinders 8 with slits that the vanes 3 extend through, are also shown. As explained above, the segments 5, 6, 7 rest against the cylinders through their outer face 30.

[0020] In the centre one of the synchronization transmission units 31 is shown. This comprises a wheel 18 and a ring 17, which have the same number of sides. The synchronization transmission will be explained in detail below.

[0021 ] The machine described above is similar to the machine described in WO 2020/159382. However, the synchronization unit has not been shown in WO 2020/159382.

[0022] Figure 5 shows a longitudinal section through the machine of figure 1 . In this figure the housing 44 is shown. One of the cylinders 8 is shown and the shaft 4 of the vane unit 1 is shown, but largely the parts inside the housing 44 has been omitted for clarity. [0023] Figure 5 shows the support disc 10 with the race 12 for the bearings 13, the end covers 40 and 11 , the large bearing 14 and the input/output shaft 15. It can here clearly be seen that the axis C of the shaft 15 is offset from the vane unit shaft 4.

[0024] Figure 5 shows two synchronization transmission units 31 and 32, each having a ring 17 and a wheel 18. These will be explained in more detail below, referring to figures 6 and 7.

[0025] Figure 6 shows an inner end portion of the shaft 15 with one of the synchronization units 32, having a ring 23 and a wheel 24.

[0026] As best shown in figure 7, the other transmission unit 31 comprises a transmission ring 17, which is supported in a bearing 16. Inside of the transmission ring 17 is arranged a transmission wheel 18. The transmission wheel 18 and the transmission ring 17 are polygonal with the same number of sides, the wheel 18 with the polygonal surface on the outside, and the ring 17 with the polygonal surface on the inside. In the shown embodiment, every second side 21 is a longer side, and every second side 22 is a shorter side. The longer sides have preferably at least twice the length of the shorter sides. As the number of sides are the same for the wheel and the ring, the corresponding sides of the wheel has to be slightly shorter than on the ring. This means that the wheel and ring will slide somewhat relative to each other when they rotate. This sliding can be made less by increasing the number of sides. However, the greater the number of sides, the wider the angle between adjoining sides will be, and the greater the risk will be that the wheel will slip relative to the ring. A synchronization transmission with more sides therefore may transfer less torque than a synchronization transmission with fewer sides.

[0027] It has been found that eight longer sides and eight shorter sides is a suitable number. However, this number may be reduced or increased depending on how high torque it is desired to transfer. It is, however, preferred that the number of sides is an even number.

[0028] The smaller sides 22 has the function of providing a larger contact surface between the wheel and the ring than a corner would have made. This will reduce the wear of the parts. [0029] In the first transmission unit 31 the transmission ring 17 is attached to the inside of the support disc 10, such as by bolts 33. The transmission wheel 18 is attached to the shaft 4 of the vane unit 1 , such as by a spline. Through the transmission wheel 18 and the transmission ring 17, rotation between the support disc 10 and the vane unit 1 can be transmitted.

[0030] The support disc 10 is supported in a large bearing 14, which in turn is arranged within the first end cover 40.

[0031 ] The first end cover 40 has an inlet port 41 for a liquid or a gas and an outlet port 42 for liquid or gas. The apparatus may be a pump to pump liquid or gas or it may be an hydraulic motor. The inlet and outlet are coupled at different places to a chamber 43 defined between the vane unit 1 and the segments 5, 6, 7 (the fluid channel between the ports 41 , 42 and the chamber is not shown). As the vane unit 1 and segments 5, 6, 7 rotates, the chamber 43 will expand on one side of the apparatus and contract on the other side.

[0032] At the opposite end of the rotation machine, there is the second synchronization transmission 32. In this second synchronization transmission 32 a transmission ring 23 is bolted to the end of the shaft 15 and a transmission wheel 24 is splined to the shaft 4 of the vane unit 1 . A set of bearings 34 supports the shaft 15 and the transmission ring in the second end cover 11.

[0033] Thrust bearings 35, 36 are arranged on each side of the transmission wheel 24 to keep this and the shaft 4 of the vane unit 1 in axial position.

[0034] The functioning of the apparatus described above will now be explained with the apparatus working as a pump.

[0035] A rotational torque is applied to the shaft 15. This rotation will be transferred to the transmission ring 23, and due to the meshing between the transmission ring 23 and the transmission wheel 24, onwards to the transmission wheel 24 and to the shaft 4 of the vane unit 1 .

[0036] At the opposite end of the shaft 4 of the vane unit 1 , is the transmission wheel 18 of the first synchronization unit 31 . Due to the meshing of this wheel 18 with the associated transmission ring 17, the support disc 10 will be set into rotation. [0037] The segments 5, 6, 7 will be set into rotation by the vane unit 1 . The vane unit 1 has a rotational axis A that is different from the rotational axis B of the segments. Moreover, the rotational axis C of the input shaft 15 may be different from the rotational axes A and B.

[0038] Figures 8 and 9 show an alternative embodiment of the ring 17 and the wheel 18, respectively of the synchronization transmission. In this embodiment, the ring and wheel has been twisted while forming the surfaces, so that the inner surfaces of the ring 17 and the outer surfaces of the wheel have a helical shape with a convex contour of each of the ring surfaces and a concave contour of each of the wheel surfaces. The advantage of this is that the running of the transmission will be smoother.

[0039] As explained previously, the synchronization transmission can be used in other types of rotation machines, such as the machine described in the above WO 2020/159381.

[0040] Figure 10 shows a piston machine that has been equipped with the synchronization unit 31 of the present invention. The machine has a housing within which is a follower 51 having cylinder bores 52. Here are four cylinder bores 52 shown. A piston 53 is arranged in each bore 52 and is allowed to travel along the bore 52. The piston 53 is coupled to a piston rod 54, which in turn is rotatably supported about a piston shaft 55 having an axis A. The follower is in turn rotatable about an axis B. The axis A is offset from axis B by a distance d. In this case the follower 51 has a common axis B with the housing 50. The piston shaft 55 and the follower shaft (not shown), and hence the axes A and B will stay in the same place during the operation of the machine while the follower and set of pistons rotate about their respective axes. The shaft 55 is coupled to a wheel 18 of a synchronization unit 31 and the follower 51 is coupled to a ring 17 of the synchronization unit 31 . Due to the synchronization unit 31 , the rotation of the shaft 55 will be in synchronicity with the follower shaft and prevent the piston rods 54 from being dragged into contact with the follower at the entrance of the bores 52. Without synchronization the piston rods 54 would hit the follower at the points 56 or 57, depending on the direction of rotation.

[0041] The machine may comprise one, two or more synchronization transmission units depending on the requirements. One synchronization transmission unit may also have two or more wheels, each meshing with a ring, where the wheels and rings, respectively, have been set at different rotational angels with respect to each other.

Claims

1 . A rotation machine having a first shaft (15; 55) and a rotor (1 ; 5, 6, 7; 51 , 53, 54), said rotor (1 ; 5, 6, 7; 51 , 53, 54) comprising a first unit (1 ; 53, 54) having a first rotation axis (A) and a second unit (5, 6, 7; 51 ) having a second rotation axis (B) different from said first rotation axis (A); said first unit (1 ; 53, 54) and said second unit (5, 6, 7; 51) being rotationally coupled via a synchronization transmission (31 ) with a 1 :1 exchange of rotation speed, characterised in that said synchronization transmission comprises an outer transmission ring (17; 23) and an inner transmission wheel (18; 24), said outer transmission ring (17; 23) having polygonal inside surface with a multiple of sides and said transmission wheel (18; 24) having a polygonal outer surface with the same number of sides as the transmission ring (17; 23); the transmission ring (17; 23) being attached to either said first unit (1 ; 53, 54) or said second unit (5, 6, 7; 51 ), and said transmission wheel (18; 24) being attached to the other one of said first unit (1 , 53, 54) and said second unit (5, 6, 7; 51 ).

2. The rotation machine according to claim 1 , characterised in that adjoining sides of said polygonal surfaces of said transmission wheel (18, 24) form an angle greater than 180°, and that adjoining sides of said polygonal surfaces of said transmission ring (17, 24) form an angle smaller than 180°.

3. The rotation machine according to claim 2, characterised in that said sides of said polygonal surfaces of said transmission ring and said transmission wheel comprises short and long sides, said short and long sides being arranged alternatingly.

4. The rotation machine according to claim 3, characterised in that said long sides have at least twice the length of said short sides.

5. The rotation machine according to any of the preceding claims, characterised in that the number of sides is an even number.

6. The rotation machine according to any of the preceding claims, characterised in that the number of sides for each of said transmission ring and said transmission wheel is between 8 and 20.

7. The rotation machine of any of the claims 2-6, characterised in that that each side of the transmission wheel (18; 24) has a smaller length than the side of the transmission ring (17; 23) which it meshes with.

8. The rotation machine according to any of the preceding claims, characterised in that said rotor (1 ; 5, 6, 7) is coupled to a wheel (24) of a second synchronization transmission unit (32) at an opposite end of the rotor (1 ; 5, 6, 7) from the first synchronization transmissions unit (31 ), and that an output or input shaft (15) is coupled to a ring (23) of said second synchronization transmission unit (32).

9. The rotation machine of claim 8, characterised in that the output or input shaft (15) has a rotational axis (C) that is different from the rotational axes (A, B) of the rotor (1 ; 5, 6, 7).

10. The rotation machine according to any of the preceding claims, characterised in that said first unit (1 ) of said rotor (1 ; 5, 6, 7) is a vane unit (1 ), comprising at least three vanes (3), and said second unit (5, 6,, 7) is a follower, comprising segments (5, 6, 7) extending between said vanes (3).

11 . The rotation machine according to any of the claims 1 -6, characterised in that said first unit of said rotor is a cylinder assembly (51 ) comprising a plurality of interconnected cylinders (52) arranged radially along at least one circle, and that said second unit of said rotor is a piston assembly (53, 54) having an equal plurality of pistons (53), one piston (53) accommodated in each of said cylinders (52); said pistons (53) being coupled to a hub (55) via an equal plurality of piston rods (54).

12. The rotation machine according to any of the preceding claims, characterised in that the wheel and the ring of the synchronization transmission have helically shaped outer surface segments, i.e. , that the wheel and the ring have a first polygonal end surface and a second polygonal end surface with straight edges, and that each side surface extends continuously between an edge of the first end surface and an edge of the second end surface and that the edges of the first and second surfaces are angularly displaced relative to one another.