An external oil pump with an idler gear

Abstract

An external oil pump with an idler gear relates to the technical field of oil pumps, and includes a main housing for installation on an engine cylinder block, an intermediate housing for installing an idler shaft fixedly connected to the left side of the main housing, a pump body fixedly connected to the left side of the intermediate housing, a central through hole opened in the axial direction of the idler shaft and a fixing bolt passed through the central through hole, one end of the fixing bolt rod extending upward from the central through hole and being tightly connected to the intermediate housing, a bushing provided on the outer sleeve of the idler shaft, an idler gear provided on the outer sleeve of the bushing, a limiting block provided in an annular manner on the outer wall of the bottom end of the idler shaft, the idler gear located between the bottom end face of the intermediate housing and the top end face of the limiting block, a driving gear meshing with the idler gear provided at the upper end of the pump body, a pump shaft installed in the pump body, one end of the pump shaft extending upward from the pump body and being coaxially fixedly connected to the driving gear. The present invention can facilitate the design of a sealing structure for the oil pump and facilitate subsequent disassembly and maintenance of the engine.

Description

Technical Field

[0001] The invention relates to the technical field of oil pumps, and in particular to an externally mounted oil pump with an idler gear. Background Art

[0002] Existing large-displacement oil pumps are usually installed in the oil pan below the engine crankcase, and the oil pump transmission gear is driven by the gear on the engine crankshaft. Since the engine crankcase is large, the center distance between the oil pump transmission shaft and the crankshaft is relatively large. Under the premise of a certain transmission ratio, if the center distance is matched by simply increasing the diameter of the oil pump transmission gear and the gear on the crankshaft, it is bound to cause the gear on the crankshaft and the oil pump transmission gear to be too large, which will increase the cost. In addition, the engine does not have enough space to arrange a gear with a large diameter. Therefore, an idler gear must be added between the oil pump transmission gear and the crankshaft gear to transmit the gear driving force on the crankshaft to the oil pump transmission gear, which can not only reduce costs but also make the engine structure more compact.

[0003] The existing oil pump with an idler gear is generally an internal pump installed in the oil pan, and the structure between the oil pump and the engine is relatively compact, which makes it very troublesome to disassemble and repair the engine later, and even requires corresponding disassembly and assembly operations of the oil pump. Summary of the invention

[0004] The object of the present invention is to provide an externally mounted oil pump with an idler gear, which can facilitate subsequent disassembly and maintenance of the engine.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: an externally mounted oil pump with an idler gear, comprising a main housing for mounting on an engine cylinder block, an intermediate housing for mounting an idler shaft fixedly connected to the left side of the main housing, a pump body fixedly connected to the left side of the intermediate housing, a central through hole opened in the axial direction of the idler shaft and a fixing bolt passed through the central through hole, one end of the fixing bolt rod extending upwardly out of the central through hole and being fastened to the intermediate housing, a bushing sleeved on the outside of the idler shaft, an idler gear sleeved on the outside of the bushing, a limiting block annularly arranged on the outer wall of the bottom end of the idler shaft, the idler gear is located between the bottom end surface of the intermediate housing and the top end surface of the limiting block, a driving gear meshing with the idler gear is arranged on the upper end of the pump body, a pump shaft is installed in the pump body, one end of the pump shaft extends upwardly out of the pump body and is coaxially fixedly connected to the driving gear, a rib annularly arranged along the outer edge of the top end of the pump body, a baffle is installed on the top end of the rib, a rotor is connected to the pump shaft located in the pump body, and a pump cover is installed at the bottom end of the pump body.

[0006] Furthermore, the intermediate housing is provided with an axial hole, the idler shaft is inserted into the axial hole and a gap is provided between the upper part thereof and the inner wall of the axial hole, the bushing is sleeved on the idler shaft located outside the axial hole, the intermediate housing is provided with an oil passage connecting the external oil circuit and the axial hole and allowing the oil to enter the gap, the center through hole is clearance-matched with the fixing bolt, the upper part of the idler shaft is provided with an upper oil hole for the oil in the gap to enter the center through hole, and the lower part of the idler shaft is provided with a lower oil hole for the oil in the center through hole to enter the idler shaft and the bushing.

[0007] Preferably, a stepped hole is formed at the bottom end of the idler gear shaft for the head of the fixing bolt to extend into, and the tightening direction of the fixing bolt when connected to the intermediate housing is opposite to the rotation direction of the idler gear.

[0008] More preferably, a pump shaft bolt is passed through the center of the driving gear, and one end of the pump shaft bolt rod is inserted downward into the pump shaft and threadedly connected to the pump shaft, so that the head of the pump shaft bolt presses the driving gear against the top end of the pump shaft.

[0009] More preferably, the bottom end surface of the driving gear is further provided with a step surface matching with the outer edge of the top end of the pump shaft.

[0010] More preferably, a sealing ring is provided between the side end of the baffle and the inner wall surface of the baffle.

[0011] More preferably, a channel for the idle gear to extend into is opened on the right portion of the baffle.

[0012] More preferably, the main housing, the intermediate housing and the pump body are an integrally formed structure made of aluminum.

[0013] The beneficial effects of the present invention are as follows: by fixing an intermediate housing on the left side of the main housing for installing the idler shaft and the idler gear, and then by fixing a pump body on the left side of the intermediate housing, the driving gear of the oil pump can be meshed with the idler gear, and the position of the oil pump can be moved to one side of the engine block, thereby achieving the purpose of installing the oil pump to the outside of the oil pan, so that when the engine needs to be disassembled and repaired later, there is no need to disassemble and assemble the oil pump, which is very convenient; not only that, after being connected to the engine block, the part of the intermediate housing is equivalent to a dark cavity, and the idler gear can easily obtain a good sealing effect in the dark cavity, thereby correspondingly facilitating the sealing design of the oil pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic cross-sectional view of the overall structure in an embodiment of the present invention;

[0015] Figure 2 It is a schematic cross-sectional view of a local structure when the fixing bolts are not included in the embodiment;

[0016] Figure 3 It is a three-dimensional schematic diagram of the bottom perspective of the overall structure in the embodiment;

[0017] Figure 4 It is a three-dimensional schematic diagram of the overall structure from the top perspective in the embodiment;

[0018] Figure 5 It is a schematic diagram of the structure of the main housing, the intermediate housing and the pump body in the embodiment;

[0019] Figure 6 Schematic diagram of the cross-sectional structure of the pump cover in the embodiment.

[0020] The accompanying drawings are marked as follows:

[0021] 1——Main housing 2——Idler shaft 2a——Center through hole

[0022] 2b——upper oil hole 2c——lower oil hole 3——middle housing

[0023] 3a——shaft hole 4——pump body 5——fixing bolt

[0024] 6 - Bushing 7 - Idle gear 8 - Drive gear

[0025] 9——Limiting block 10——Baffle 11——Rotor

[0026] 12——Pump cover 13——Pump shaft bolt 14——Sealing ring

[0027] 15——Ring 16——Oil channel 17——Pump shaft

[0028] 18——Groove. DETAILED DESCRIPTION

[0029] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the implementation modes are not intended to limit the present invention.

[0030] It should be noted in advance that, in the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In addition, in the present invention, unless otherwise clearly specified and limited, the first feature "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them instead of being in direct contact. Moreover, the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature. The terms "above", "below", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention.

[0032] like Figure 1-5 As shown, an externally mounted oil pump with an idler gear comprises a main housing 1 for mounting on an engine cylinder block, an intermediate housing 3 for mounting an idler shaft 2 is fixedly connected to the left side of the main housing 1, a pump body 4 is fixedly connected to the left side of the intermediate housing 3, the idler shaft 2 is provided with a central through hole 2a in the axial direction and a fixing bolt 5 is passed through the central through hole 2a, one end of the rod of the fixing bolt 5 extends upwardly out of the central through hole 2a and is fastened to the intermediate housing 3, a bushing 6 is sleeved on the outside of the idler shaft 2, an idler gear 7 is sleeved on the outside of the bushing 6, and the idler A limit block 9 is annularly arranged on the outer wall at the bottom end of the shaft 2, and the idle gear 7 is located between the bottom end surface of the intermediate housing 3 and the top end surface of the limit block 9. A driving gear 8 meshing with the idle gear 7 is provided at the upper end of the pump body 4. A pump shaft 17 is installed in the pump body 4, and one end of the pump shaft 17 extends upward from the pump body 4 and is coaxially fixedly connected with the driving gear 8. A rib 15 is annularly arranged along the outer edge of the top end of the pump body 4, and a baffle 10 is installed at the top end of the rib 15. A rotor 11 is connected to the pump shaft 17 located in the pump body 4, and a pump cover 12 is installed at the bottom end of the pump body 4.

[0033] The external oil pump with an idler gear provided in the above embodiment, after the main housing 1 is installed and connected with the engine cylinder block, the power gear on the engine output shaft can be located in the main housing 1 and meshed with the idler gear 7 in the intermediate housing 3, thereby realizing power transmission. Since the idler shaft 2 and the idler gear 7 are installed in the intermediate housing 3 on one side of the main housing 1, and then the pump body 4 is fixedly connected on the left side of the intermediate housing 3, the driving gear 8 of the oil pump can be meshed with the idler gear 7, and the position of the oil pump can be moved to one side of the engine cylinder block, thereby achieving the purpose of installing the oil pump to the outside of the oil pan. In this way, when the engine needs to be disassembled and repaired later, there is no need to disassemble and assemble the oil pump, which is very convenient. Not only that, after being connected to the engine cylinder block, the part of the intermediate housing 3 is equivalent to a dark cavity, and the idler gear 7 can easily obtain a good sealing effect in the dark cavity, and the idler gear 7 and the driving gear 8 are invisible in appearance.

[0034] It is worth noting that, since the idle gear 7 is located between the limit block 9 and the bottom end of the intermediate housing 3, the gap between the end face of the idle gear 7 and the bottom end face of the intermediate housing 3 can be controlled by changing the thickness of the limit block 9. Figure 5 As shown, a 2 mm thick boss may be designed at the bottom end of the intermediate housing 3 , and the diameter of the boss is slightly larger than the diameter of the end face of the idle gear 7 , so that the idle gear 7 can be easily contacted or supported.

[0035] Furthermore, the intermediate housing 3 is provided with an axial hole 3a, the idler shaft 2 is inserted into the axial hole 3a and a gap is provided between the upper part thereof and the inner wall of the axial hole 3a, the bushing 6 is mounted on the idler shaft 2 located outside the axial hole 3a, and the intermediate housing 3 is provided with an oil passage 16 which connects the external oil circuit with the axial hole 3a and allows oil to enter the gap, the center through hole 2a is clearance-matched with the fixing bolt 5, the upper part of the idler shaft 2 is provided with an upper oil hole 2b for allowing the oil in the gap to enter the center through hole 2a, and the lower part of the idler shaft 2 is provided with a lower oil hole 2c for allowing the oil in the center through hole 2a to enter between the idler shaft 2 and the bushing 6. Those skilled in the art should know that the external oil circuit connected to the oil passage 16 is an oil circuit led from the pump outlet, and by introducing the oil between the idler shaft 2 and the bushing 6, a good lubrication effect can be achieved on the outer surface of the idler shaft 2 and the inner surface of the bushing 6.

[0036] Preferably, a stepped hole is provided at the bottom end of the idler shaft 2 for the head of the fixing bolt 5 to extend into. The tightening direction of the fixing bolt 5 when connected to the intermediate housing 3 is opposite to the rotation direction of the idler gear 7, and the length of the connecting portion between the fixing bolt 5 and the intermediate housing 3 is at least twice the diameter of the rod of the fixing bolt 5, and the portion of the intermediate housing 3 into which the fixing bolt 5 extends is a blind hole structure, which can avoid the need for additional design of a sealing structure.

[0037] As a more preferred embodiment, a pump shaft bolt 13 is inserted through the center of the driving gear 8, and one end of the rod of the pump shaft bolt 13 is inserted downward into the pump shaft 17 and is threadedly connected with the pump shaft 17, so that the head of the pump shaft bolt 13 presses the driving gear 8 against the top of the pump shaft 17, and the tightening direction of the pump shaft bolt 13 is opposite to the rotation direction of the driving gear 8. The method of fastening the connection with the pump shaft bolt 13 can facilitate rework and repair. In addition, the use of the pump shaft bolt 13 can improve the connection reliability and avoid the problem of insufficient clamping force caused by the interference fit with the pump shaft 17 when the driving gear 8 is too thin. Among them, the bottom end surface of the driving gear 8 is also provided with a step surface that matches the outer edge of the top of the pump shaft 17.

[0038] It should be noted that the oil pump in this embodiment is a rotor type oil pump, and the inner rotor is connected to the pump shaft 17 . The outer part of the inner rotor is also connected to the outer part of the inner rotor, and the inner rotor and the pump shaft 17 are interference fit.

[0039] As a more preferred embodiment, a sealing ring 14 is provided between the side end of the baffle 10 and the inner wall surface of the rib 15, and a passage for the idler gear 7 to extend into is provided at the right portion of the baffle 10. Of course, a sealing ring can also be provided at the connection between the pump body 4 and the pump cover 12, thereby further improving the sealing effect of the external pump structure.

[0040] In addition, in this embodiment, Figure 5 As shown, the main housing 1, the intermediate housing 3 and the pump body 4 are an integrally formed structure made of aluminum parts, which has a good sealing effect. Moreover, since the idler gear 7 is threadedly connected to the aluminum parts through the fixing bolts 5, the firmness is effectively improved and it is more adaptable to the aluminum part structure.

[0041] In addition, the pump cover 12 of the oil pump in the above embodiment may be provided with a groove 18 for the bottom end of the pump shaft 17 to extend into, such as Figure 6 As shown, the pump cover 12 is provided with an oil inlet, and the bottom of the groove 18 can be designed with an oil leakage channel connected to the oil inlet, so that the lubricating oil between the groove 18 and the pump shaft 17 can be leaked into the low-pressure chamber of the oil pump.

[0042] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention may also be implemented in other ways. Any obvious replacement without departing from the concept of the present technical solution is within the protection scope of the present invention.

[0043] In order to make it easier for ordinary technicians in the field to understand the improvements of the present invention over the prior art, some drawings and descriptions of the present invention have been simplified, and for the sake of clarity, some other elements are omitted in this application document. Ordinary technicians in the field should realize that these omitted elements may also constitute the content of the present invention.

Claims

1. An externally mounted oil pump with an idler gear, characterized in that: The invention comprises a main housing (1) for mounting on an engine cylinder block, an intermediate housing (3) for mounting an idler shaft (2) being fixedly connected to the left side of the main housing (1), a pump body (4) being fixedly connected to the left side of the intermediate housing (3), the idler shaft (2) being provided with a central through hole (2a) in the axial direction, a fixing bolt (5) being passed through the central through hole (2a), one end of the rod of the fixing bolt (5) extending upwardly out of the central through hole (2a) and being fastened to the intermediate housing (3), a bushing (6) being sleeved on the outside of the idler shaft (2), an idler gear (7) being sleeved on the outside of the bushing (6), a limiting block (9) being annularly arranged on the outer wall of the bottom end of the idler shaft (2), the idler gear (7) being located between the bottom end surface of the intermediate housing (3) and the top end surface of the limiting block (9), a driving gear (8) meshing with the idler gear (7) being arranged on the upper end of the pump body (4), a pump shaft (17) being installed in the pump body (4), and one end of the pump shaft (17) being The pump body (4) extends upward and is coaxially fixedly connected to the driving gear (8). The top of the pump body (4) is provided with a rib (15) in an annular manner along its outer edge. A baffle (10) is installed at the top of the rib (15). A rotor (11) is connected to a pump shaft (17) located in the pump body (4). A pump cover (12) is installed at the bottom end of the pump body (4). A pump shaft bolt (13) is passed through the center of the driving gear (8). One end of the rod of the pump shaft bolt (13) is extended to the bottom end of the pump body (4). The pump shaft (17) is inserted into the pump shaft (17) and is threadedly connected to the pump shaft (17), so that the head of the pump shaft bolt (13) presses the driving gear (8) against the top end of the pump shaft (17), a sealing ring (14) is provided between the side end of the baffle (10) and the inner wall surface of the rib (15), and a channel for the idler gear (7) to extend into is provided on the right part of the rib (15), and the main housing (1), the intermediate housing (3) and the pump body (4) are an integrally formed structure made of aluminum parts.

2. The externally mounted oil pump with an idler gear according to claim 1, characterized in that: The intermediate housing (3) is provided with an axial hole (3a), the idler shaft (2) is inserted into the axial hole (3a) and a gap is provided between the upper part of the idler shaft (2) and the inner wall of the axial hole (3a), the bushing (6) is sleeved on the idler shaft (2) located outside the axial hole (3a), the intermediate housing (3) is provided with an oil passage (16) which connects the external oil passage with the axial hole (3a) and allows oil to enter the gap, the central through hole (2a) is clearance-matched with the fixing bolt (5), the upper part of the idler shaft (2) is provided with an upper oil hole (2b) for allowing oil in the gap to enter the central through hole (2a), and the lower part of the idler shaft (2) is provided with a lower oil hole (2c) for allowing oil in the central through hole (2a) to enter between the idler shaft (2) and the bushing (6).

3. The externally mounted oil pump with an idler gear according to claim 2, characterized in that: The bottom end of the idler gear shaft (2) is provided with a stepped hole into which the head of the fixing bolt (5) can be inserted. The tightening direction of the fixing bolt (5) when connected to the intermediate housing (3) is opposite to the rotation direction of the idler gear (7).

4. The externally mounted oil pump with an idler gear according to claim 3, characterized in that: The bottom end surface of the driving gear (8) is also provided with a step surface that matches the outer edge of the top end of the pump shaft (17).

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