GB2543328A

GB2543328A - Transmission

Info

Publication number: GB2543328A
Application number: GB1518241.3A
Authority: GB
Inventors: Tuexen Thorsten; Graumueller Robert; Wachtel Udo
Original assignee: Caterpillar Motoren GmbH and Co KG
Current assignee: Caterpillar Motoren GmbH and Co KG
Priority date: 2015-10-15
Filing date: 2015-10-15
Publication date: 2017-04-19
Also published as: DE102016119361A1; GB201518241D0

Abstract

A transmission 1 to drive both a first ancillary unit 101 and a second ancillary unit 102. The transmission 1 comprises a first unit gear 8 to drive ancillary unit 101, a second unit gear 9 to drive the second ancillary unit 102, and a first idler gear 6 to be driven by a crankshaft gear 5. The first unit gear 8 meshes with the first idler gear 6. The ancillary unit gears are positioned, to allow placement of a second idler gear 7 between the ancillary unit gears to connect the ancillary unit gears 8 and 9. It is also possible to place idler gear 7 between the unit gear 9 and the idler gear 6 to connect the second ancillary unit gear 9 and the first idler gear 6. Repositioning of the second idler gear 7 allows a choice of rotational direction for whatever ancillary unit is being driven by the second ancillary unit gear. Also disclosed is a similar transmission using a single idler gear (figs 4 & 5)

Description

TRANSMISSION

Technical Field [0001] The present disclosure relates to a transmission for an internal combustion engine to drive both a first ancillary unit and a second ancillary unit. The present disclosure relates further to an engine including a transmission.

Background [0002] Ancillary units are devices related to the engine to operate the engine. Such ancillary units may be fuel pumps, cooling fluid pumps etc. Fuel pumps are used to pressurize the fuel, so the fuel may be injected in a cylinder of the engine for combustion. Pumps for the cooling fluid may be used to transport the cold cooling fluid to the engine and/or to transport the heated cooling fluid from the engine to a heat exchanger for example.

[0003 ] These ancillary units may be driven by a crankshaft of the engine. The crankshaft of the engine may be connected to input shafts of the ancillary units by connection means like gears and belts to transmit torque from the crankshaft to the input shafts of the ancillary units.

[0004] EP 2 357 338 B1 discloses a diesel engine laterally mounted on a vehicle body. Attached to the diesel engine are an oil pump and a fuel pump, which are driven by a crankshaft of the engine using a transmission. To drive the oil pump a first idler gear meshes with a crank gear supported by the crankshaft, the first idler gear meshes with a first balancer shaft gear and the first balancer shaft gear meshes with an oil pump gear supported by a drive shaft of the oil pump.

[0005] A drive shaft of the fuel pump supports a fuel pump gear which meshes with a second idler gear. The second idler gear meshes with the first idler gear, which is driven by the crankshaft.

[0006] However EP 2 357 338 does not take into account a situation in which the transmission may need to adapt to a different direction of rotation of the crankshaft.

[00071 The present disclosure is directed, at least in part, to improving or overcoming one or more aspects of prior systems.

[0008]

Summary of the Disclosure [0009] In an aspect of the present disclosure, a transmission is provided to drive both a first ancillary unit and a second ancillary unit.

[0010] The transmission includes a first gear to drive the first ancillary unit, a second gear to drive the second ancillary unit and a third gear to be driven by a crankshaft of an engine. The first gear meshes with the third gear.

[0011 ] The first gear and the second gear are positioned, so it is possible to place a fourth gear between the first gear and the second gear to connect the first gear with the second gear as well as to place the fourth gear between the second gear and the third gear to connect the second gear and the third gear.

[0012] Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

Brief Description of the Drawings [00131 The accompanying drawings, which are incorporated herein and constitute a part of the specification, illustrate exemplary embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure. In the drawings: [0014] FIG. 1 illustrates an engine; [0015] FIG. 2 illustrates an exemplary transmission, in accordance with an embodiment of the present disclosure; [0016] FIG. 3 illustrates the transmission of FIG. 1 in a second configuration; [0017] FIG. 4 illustrates a further exemplary transmission, in accordance with an embodiment of the present disclosure; and [0018] FIG. 5 illustrates the transmission of FIG. 3 in a second configuration.

Detailed Description [0019] FIG 1 discloses an engine 100, comprising a crankshaft 2 and a crank case 103. A crankshaft gear 5 is connected to the crankshaft 2, so the crankshaft gear 5 rotates together with the crankshaft 2. A first ancillary unit 101 and a second ancillary 102 unit are positioned at the front end of the crank case 103, to be driven by the crankshaft 2. The ancillary unit 101, 102 may be for example a fuel pump, a high pressure pump, an oil pump, a circulation pump, alternator, generator, compressor, water pump, etc. The torque of the crankshaft 2 is transmitted by a transmission 1 with the gear 5 and gears 6, 7, 8 and 9 to a drive shaft 3 of the first ancillary unit 101 and a drive shaft 4 of the second ancillary unit 102.

[0020] FIG. 2 discloses the transmission 1 to transfer rotational energy from a crankshaft 2 to the drive shaft 3 of a first ancillary unit lOland to the drive shaft 4 of the second ancillary unit 102. The crankshaft 2 supports the crankshaft gear 5. The crankshaft gear 5 meshes with a first idler gear 6. The first idler gear 6 meshes with the second idler gear 7 and the first ancillary unit gear 8, which is supported by the drive shaft 4 of the first ancillary unit 101. The second idler gear 7 meshes with the second ancillary unit gear 9 supported by the drive shaft 4 of the second ancillary unit 102.

[0021] The crankshaft gear 5 may be mechanically connected to the crankshaft 2, in particular connected in a manner in which the crankshaft 2 cannot rotate with respect to the crankshaft gear 5. The connection may be by welding, form fit, force fit, or joined integrally.

[0022] The drive shaft 3 of the first ancillary unit 101 and the drive shaft 4 of the second ancillary unit 102 may be mechanically connected to the first ancillary unit gear 8 and the second ancillary unit gear 9 such that the drive shaft 3 of the first ancillary unit 101 and/or the drive shaft 4 of the second ancillary unit 102 cannot rotate with respect to the first ancillary unit gear 8 and/or the second ancillary unit gear 9.

[0023] A rotational axis 10 of the drive shaft 4 of the second ancillary unit may also be the rotational axis 10 of the second ancillary unit gear 9. A rotational axis 13 of the drive shaft 3 of the first ancillary unit may also be the rotational axis 13 of the first ancillary unit gear 8. A rotational axis 14 of the crankshaft 2 may also be the rotational axis 14 of the crankshaft gear 5.

[0024] The rotational axes 10, 11, 12, 13 and 14 may be parallel with each other, and the gears 5, 6, 7, 8 and 9 may be arranged in the same plane. The gears may be spur gears, internal gears, crown wheels etc.

[0025] The transmission 1 may have a housing 15, which may cover the transmission 1. The housing 15 may be at least partly integral with an engine block of the engine. The housing 15 may include a first fixation element 16 to rotatably connect the second idler gear 7 to the housing 15 in a first position, so that the second idler gear 7 meshes with the second ancillary unit gear 9 and with the first idler gear 6. The housing 15 may include a second fixation element 17 to rotatably connect the second idler gear 7 to the housing 15 in a second position, so that the first idler gear 6 meshes with the first ancillary unit gear 8 and with the second ancillary unit gear 9. The fixation element may be a shaft on which the second idler gear 7 may be positioned.

[0026] According to another embodiment the first idler gear 6 may be connected to the crankshaft gear 5 by one or more torque transmission units, such as gears, belts, etc.

[0027] FIG. 3 shows the transmission 1 of Fig. 1 but with second idler gear 7 removed from the first position and positioned rotatably in the second position on the second fixation element 17. The second idler gear 7 now meshes with the first ancillary unit gear 8 and the second ancillary unit gear 9, transmitting torque from the first ancillary unit gear 8 to the second ancillary unit gear 9. In this configuration, the first ancillary unit gear 8 and the second ancillary unit gear 9 rotate in the direction of rotation of the crankshaft gear 5.

[0028] At least the first idler gear 6, the first ancillary unit gear 8, the second idler gear 7 and the second ancillary unit gear 9 are encompassed by the housing 15, to shield the transmission 1 from mechanical impact and contain lubrication inside the housing. The crankshaft gear 5 may also be inside the housing 15. The housing 15 provides enough space to place the second idler gear 7 selectively in the first position or the second position.

[0029] FIG. 4 shows an alternate embodiment of transmission 1. The crankshaft gear 5 meshes with the first ancillary unit gear 8. The first ancillary unit gear 8 meshes with the second idler gear 7, which is positioned in a second position 19. The second idler gear 7 meshes with the second ancillary unit gear 9. The second idler gear 7 may be rotatably connected to the housing 15 by the second fixation element 17. In this configuration the first ancillary unit rotates in a counter direction with respect to the crankshaft gear 5. The second idler gear 7 rotates in the same direction as the crankshaft gear 5 and the second ancillary unit gear 9 rotates in a counter direction with respect to the crankshaft gear 5.

[0030] FIG. 5 shows the transmission 1 of FIG. 3 in a second configuration. The second idler gear 7 is arranged in a first position 18 meshing with the crankshaft gear 5 and the second ancillary unit gear 9. The first ancillary unit gear 8 meshes with the crankshaft gear 5.

Industrial Applicability [0031] To drive a first ancillary unit like a recirculation pump and a second ancillary unit like a high pressure pump by the crankshaft 2, the crankshaft gear 5 meshes as shown in FIG. 2 with the first idler gear 6. The first idler gear 6 rotates in a counter direction with respect to the crankshaft gear 5. The first idler gear 6 meshes with the second idler gear 7 and the first ancillary unit gear 8. The second idler gear 7 and the first ancillary unit gear 8 rotate in the same direction as the crankshaft gear 5. The second idler gear 7 meshes with the second ancillary unit gear 9, so that the second ancillary unit gear 9 rotates in a counter direction with respect to the crankshaft gear 5. If the engine 100 is configured to rotate in a counter direction with respect to the above-described first configuration, the crankshaft 5 will rotate during operation in the counter direction. To rotate the drive shaft 4 of the second ancillary unit in the same direction as in the first configuration, the second idler gear may be arranged in the second position, so the second idler gear 7 meshes with the first ancillary unit gear 8 and the second ancillary unit gear 9. In this configuration the second ancillary unit gear 9 rotates in the same direction as the crankshaft gear 5. Since ancillary units such as high pressure pumps may have a preferred direction of rotation, the transmission 1 may allow a change of position of the second idler gear 7 from a first position 18 to a second position 19, when changing the rotational direction of the engine.

Claims

Claims What is claimed is:

1. Transmission (1) to drive both a first ancillary unit (101) and a second ancillary unit (102), comprising: a first ancillary unit gear (8) to drive the first ancillary unit (101), a second ancillary unit gear (9) to drive the second ancillary unit (102) and a first idler gear (6) to be driven by a crankshaft gear (5) of an engine (100); wherein the first ancillary unit gear (8) meshes with the first idler gear (6); and the first ancillary unit gear (8) and the second ancillary unit gear (9) are positioned, so it is possible to place a second idler gear (7) between the first ancillary unit gear (8) and the second ancillary unit gear (9) to connect the first ancillary unit gear (8) with the second ancillary unit gear (9) as well as to place the second idler gear (7) between the second ancillary unit gear (9) and the first idler gear (6) to connect the second ancillary unit gear (9) and the first idler gear (6).

2. Transmission (1) of claim 1, wherein the first ancillary unit is a circulation pump.

3. Transmission (1) of one of the preceding claims, wherein the transmission includes a housing (15) which houses the first ancillary unit gear (8), the second ancillary unit gear (9), the first idler gear (6) and a second idler gear (7).

4. Transmission (1) of claim 3, wherein the housing (15) includes a first mount to hold the second idler gear (7) at a first position between the first ancillary unit gear (8) and the second ancillary unit gear (9) and a second mount to hold the second idler gear (7) at a second position between the second ancillary unit gear (9) and the first idler gear (6).

5. Transmission (1) of one of the preceding claims, wherein the second ancillary unit (102) is a high pressure pump.

6. Transmission (1) of one of the preceding claims, wherein the first idler gear (6) is connected to the crankshaft (2) and rotatable around a main longitudinal axis (14) of the crankshaft (2).

7. Transmission (1) of one of the preceding claims, wherein the first ancillary unit gear (8) is connected to a first ancillary unit drive shaft (3).

8. Transmission (1) of one of the preceding claims, wherein the second ancillary unit gear (9) is connected to a second ancillary unit drive shaft (4).

9. Transmission (1) of one of the preceding claims, wherein the first ancillary unit gear (8), the second ancillary unit gear (9), the first idler gear (6) and the second idler gear (7) are arranged in a common plane.

10. Transmission (1) of one of the preceding claims, wherein: in a first configuration, the first ancillary unit gear (8) meshes with the first idler gear (6) and the second idler gear (7); and the second ancillary unit gear (9) meshes with the first idler gear (6); and in a second configuration, the first ancillary unit gear (8) meshes with the first idler gear (6); and the second idler gear (7) meshes with the second ancillary unit gear (9) and the first idler gear (6).

11. Transmission (1) of claim 10, wherein the second idler gear (7) is rotatably and detachably connected to the housing (15).

12. Engine comprising a transmission (1) of one of the preceding claims.