JPH04105697U - oil pump - Google Patents

Abstract

(57) [Summary] [Purpose] To maintain good sealing performance of the oil seal and prevent it from accidentally falling off by reducing the outward pressing force of the oil seal due to the lubricating oil in the seal chamber. [Structure] The lubricating oil circulating in the rotational direction of the drive shaft 3 is transferred to a position forward of the opening 12a at one end of the drain hole 12 in the seal chamber 11 of the pump casing 1 in the drain hole 1.
In this configuration, a guide member 14 for forcibly guiding the lubricating oil is provided in the seal chamber 11, and a dam member 13 is provided in the seal chamber 11 to prevent the lubricating oil from flowing in the direction of the oil seal 9.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This idea was developed to improve the oil pump that pumps lubricating oil to each sliding part of an internal combustion engine. related.

0002

[Conventional technology]

A conventional oil pump of this type uses a so-called internal gear as shown in Fig. 7, for example. Type oil pumps are known (see Japanese Utility Model Application Publication No. 126506/1983, etc.).

0003 To explain the outline, 1 in the figure is a pump case whose opening end is closed by a cover 2. 3 is a drive shaft passing through substantially the center of the pump casing 1 and the cover 2; , 5 is an engine rotatably housed in the circular working chamber 6 of the pump casing 1. an inner gear and an outer gear, and the inner gear 4 is connected to the drive shaft 3. The ring-shaped outer gear 5 has an outer ring on its outer periphery that meshes with the inner teeth of the ring-shaped outer gear 5. teeth are formed. In addition, a spigot-type collar is provided on one side of the inner gear 4. A peripheral surface 7a of this collar portion 7 and a supporting surface 7 in the thrust direction are formed. A predetermined hole b is formed on the bearing surface 8a of the bearing portion 8 formed approximately at the center of the casing 1. It is slidably supported via balance C. 9 in the figure is pump casing 1. Between the inner circumferential surface 10a of the annular portion 10 on one side and the outer circumferential surface 3a of the drive shaft 3 This is an annular oil seal arranged inside the oil seal 9 (left side). is a circle for temporarily storing the lubricating oil leaked from the working chamber 6 through the clearance C. An annular seal chamber 11 is formed. Also, 12 is inside the lower end of the casing 1. This drain hole 12 is formed to penetrate approximately along the diameter direction. The lubricating oil in the oil chamber 11 is introduced from the opening 12a at one end and externally from the opening 12b at the other end. (inside the oil pan).

0004

[Problem that the idea aims to solve]

By the way, as the inner gear 4 and outer gear 5 rotate, leakage occurs from the working chamber 6. The lubricating oil that passed through the clearance C while lubricating the bearing part 8 remains in the seal chamber. 11, and here, along with the rotation of the drive shaft 3, it is entrained in the direction of rotation. rotate. Therefore, especially when the drive shaft 3 rotates at high speed, the inertia of the lubricating oil itself Due to this, the water passes through the opening 12a of the drain hole 12. For this reason, the seal It becomes difficult for lubricating oil to flow from the chamber 11 to the drain hole 12, and as a result, the seal chamber 1 The pressure of the entire oil seal 9 increases, and a strong outward pressing force is applied to the entire oil seal 9, causing the oil seal to close. The oil seal performance may deteriorate, causing lubricating oil to leak, or in some cases, the oil seal 9 itself may be damaged on the outside. There is a problem that it can slip out.

[0005]

[Means to solve the problem]

This invention was devised in view of the above-mentioned conventional problems, and it is based on the first claim. The idea is that the area is located in front of the opening at one end of the drain hole in the seal chamber in the direction of rotation of the drive shaft. A guide member is provided at the opposite position, and one end opening of the drain hole in the seal chamber and the oil It is characterized by the provision of a dam member between it and Lucille.

[0006] The invention according to the second claim is particularly advantageous due to the opening of one end of the drain hole at the end of the inner gear. A scraping member with its tip facing into the seal chamber is installed at the rear of the drive shaft in the rotational direction. It is characterized by

[0007]

[Effect]

According to the invention of the first claim, the pump can be removed from inside the pump casing during pump operation. The lubricating oil that has flowed into the seal chamber through between the casing and the drive shaft prevents the drive shaft from rotating. As it rotates, it begins to swirl in the direction of rotation, but this swirling flow hits the guide member. The turning force is suppressed, and the side surface of the guide member quickly flows into the drain hole. The increase in pressure inside the sealing chamber is suppressed. Also, it may flow into the seal chamber. The lubricating oil is prevented from flowing in the direction of the oil seal by the dam member, so it Together with the action of the guide member, the outward pressing force on the oil seal is sufficiently low. down.

[0008] According to the invention of the second claim, the flow from inside the pump casing toward the seal chamber. The lubricating oil is forcibly scraped off by a scraping member installed at the end of the inner gear. It is collected and immediately guided into the drain hole as it is. Therefore, into the seal chamber The inflow of lubricating oil is reduced, and the increase in oil pressure is suppressed.

[0009]

【Example】

Hereinafter, each embodiment of this invention will be described in detail based on the drawings. In addition, common to the above conventional Constituent parts will be described with the same reference numerals.

0010 1 to 3 show an embodiment corresponding to the invention of the first claim. The pump casing is closed by the pump cover 2, 3 is the drive shaft, and 4 is the pump casing. An engine rotatably housed in the working chamber 6 in the housing 1 and connected to the drive shaft 2. The inner gear 5 has internal teeth that mesh with the external teeth of the inner gear 4, and whose axis is aligned with the inner gear. A ring-shaped outer gear eccentric to the axis of 4, 7 is at one end of inner gear 4 is provided and slides on the bearing part 8 of the pump casing 1 through a clearance C. A freely supported collar portion 9 is an annular portion 10 integrally formed on the outer end side of the bearing portion 8. An annular ring disposed between the stepped large-diameter inner circumferential surface 10a and the outer circumferential surface 3a of the drive shaft 3. An oil seal, 11 is a seal chamber formed inside the oil seal 9, and 12 is a port. An opening 12a is formed in the pump casing 1, and an opening 12a is connected to the seal chamber 11 at one end, and an opening 12a at one end is connected to the seal chamber 11. The end openings 12b are drain holes provided outside (inside the crankcase).

[0011] A dam member 13 is fixed to the inner end surface 10a of the annular portion 10, and A guide member 14 is integrally provided at a predetermined position of the dam member 13. That is, before The dam member 13 is arranged to cover the inner end surface of the oil seal 9, as shown in FIGS. 2A and 2B. It is formed in the shape of an annular plate, and has an insertion hole 13a for the drive shaft 3 formed in the center. The outer peripheral edge is press-fitted and fixed to the stepped diameter portion of the inner peripheral surface 10a inside the oil seal 9. One side surface 13b on the working chamber 6 side is approximately at the outer hole edge of one end opening 12a of the drain hole 12. are placed facing each other.

0012 On the other hand, the guide member 14 is formed into a rectangular plate shape, and one side edge is above and below the dam member 13. It is fixed to the lowermost end on the center line and provided along the axial direction of the drive shaft 3. Two This guide member 14 crosses the sealing chamber 11 at the lowermost end of the dam member 13. The drive shaft 3 is provided in a shape in front of the opening 12a at one end of the drain hole 12 in the rotational direction of the drive shaft 3. The tip 14a is oriented perpendicularly toward the axis of the drive shaft 3. are doing.

[0013] Therefore, according to this embodiment, a clear run is made from inside the working chamber 6 during pump operation. The lubricating oil that has flowed into the seal chamber 11 through the SC is transferred to the drive shaft 3 as shown in FIG. As it rotates in the direction of the arrow in Figure 1, it begins to rotate in the direction of rotation, but the lubrication Due to its own inertia, some of the oil crosses over the opening 12a at one end and reaches the guide member. collides with one side 14b of 14. Therefore, the turning force of the lubricating oil is regulated here, As it is, it is immediately guided into the drain hole 12 from the opening 12a along the one side 14b. It is then returned to the oil pan (not shown). Therefore, the oil pressure inside the seal chamber 11 rise is sufficiently suppressed.

[0014] Moreover, as described above, the lubricating oil that has flowed into the seal chamber 11 is removed by the dam member 13. This effectively prevents the lubricating oil from flowing in the direction of the oil seal 9, and the swirling flow of the lubricating oil is As shown in FIG. 3, since it is carried out inside the dam member 13, The dam member 13 reliably limits the outward pressing force on the oil seal 9 due to It will be done. Therefore, in conjunction with the action of the guide member 14, the oil seal 9 is The outward pressing force is sufficiently reduced. As a result, the oil seal 9 has a good seal. The performance is maintained and the oil seal 9 is prevented from coming off inadvertently.

[0015] Further, in this embodiment, the dam member 13 and the guide member 14 are integrally formed in advance. Therefore, the assembly work to the pump casing 1 is relatively easy. In addition, Guy Since the door member 14 is formed separately from the pump casing 1, the seal chamber 1 1 is added to the oil pump in which one end opening 12a of the drain hole 12 is formed. It is easy to

[0016] 4 to 6 show an embodiment corresponding to the invention of the second claim, and in this embodiment, the drain The hole is located not in the pump casing 1 but at the connection point between the drive shaft 3 and the inner gear 4. It is something that is being criticized.

[0017] That is, the drive shaft 3 has a width across flats 3b, at both diametrical ends of a portion located in the working chamber 6. 3c is formed on the inner peripheral surface of the drive shaft insertion hole 4a of the inner gear 4. Widths across flats 4b and 4c corresponding to widths across flats 3b and 3c are formed, and width across flats 4b , 4c, a pair of drain grooves 15, 15 are formed along the axial direction approximately in the center of the drain grooves 15, 4c. The drain grooves 15, 15 have openings 15a, 15a at one end connected to the seal chamber 11, and openings 15a at the other end. The opening faces into the crankcase.

[0018] In addition, a pair of protruding scraping members 16, 16 are provided at the tip of the collar portion 7 of the inner gear 4. are integrated. To be more specific, the scraping members 16, 16 are One end edge of the width across sides 4b, 4c, that is, one end opening 15a, 1 of the drain groove 15, 15. 5a in the rotational direction of the drive shaft 3, and its tip portion 16a, 16a faces into the seal chamber 11, and side edges 16b, 16b face each drain. The grooves 15, 15 are bent on the axis center line side.

[0019] In addition, 17 and 18 in Fig. 6 are the suction chambers provided on both sides of the pump casing 1. and the discharge chamber.

[0020] Therefore, according to this embodiment, the clearing liquid is removed from the working chamber 6 while the pump is rotating. The lubricating oil that was about to flow into the seal chamber 11 through the inner gear 4 The tip portion 16a and side edge portion 16b of the scraping members 16, 16 that rotate together The drain groove is forcibly collected from the openings 15a and 15a at each end. 15, 15. Therefore, lubricating oil enters the seal chamber 11. The inflow amount decreases, and as a result, the rise in the oil pressure inside the seal chamber 11 is suppressed, and the oil pressure increases. The outward pressing force on the roller 9 is reduced.

[0021] In particular, in this embodiment, the lubricating oil is forcibly scraped off by the scraping members 16, 16. In order to actively feed the water into the drain grooves 15, 15, the oil pressure inside the seal chamber 11 increases. can be effectively suppressed.

[0022] Additionally, the lubricating oil that has already flowed into the seal chamber 11 is forcibly scraped up and removed. Since it can be fed into the cylinder grooves 15, 15, the oil pressure in the seal chamber 11 can be reduced. becomes extremely large.

[0023] Furthermore, in this embodiment, the drain grooves 15, 15 are located not in the pump casing 1, but in the pump casing 1. Since the width across flats 4b and 4c of the inner gear 4 were formed by cutting, the machining work was It is relatively easy and advantageous in terms of manufacturing cost.

[0024] It should be noted that each invention is not limited to the configuration of each embodiment, for example, the configuration of the second claim. In the embodiment, the scraping member is provided at the end of the inner gear that does not have a collar part. is also possible.

[0025]

[Effect of the idea]

As is clear from the above explanation, according to each invention according to each claim, the pump casing Guides the lubricating oil that has flowed into the seal chamber from the plug or is about to flow into the seal chamber. It is forcibly guided to each drain hole by a member or scraping member and quickly released to the outside. The dam member prevents lubricating oil from flowing into the oil seal side. As a result, the pressure inside the seal chamber decreases and the oil seal The direct outward pressing force of This results in a good sealing of the oil seal. Not only can performance be maintained, but the oil seal can also be reliably prevented from accidentally slipping out. .

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an oil pump showing an embodiment corresponding to the invention of claim 1.

FIG. 2A is a front view showing the dam member and guide member of this embodiment, and B is a side view of the same dam member and guide member.

FIG. 3 is an enlarged view of the main parts of this embodiment.

FIG. 4 is a sectional view taken along the line A-A in FIG. 6, showing an embodiment corresponding to the invention of the first claim.

FIG. 5 is a rear view of the inner gear used in this embodiment.

FIG. 6 is a front view showing the oil pump of this embodiment.

FIG. 7 is a longitudinal sectional view showing a conventional oil pump.

[Explanation of symbols]

1...Pump casing 3...Drive shaft 4...Inner gear 5...Outer gear 9...Oil seal 11... Seal chamber 12...Drain hole 12a...One end opening 13...Dam member 14...Guide member 15...Drain groove (drain hole) 15a...One end opening 16...Scraping member 16a...Tip part

Claims (2)

[Scope of utility model registration request] 1. A pump casing that rotatably houses an inner gear and an outer gear that mesh with each other; a drive shaft that passes through a substantially central portion of the pump casing and is connected to the inner gear; and the pump casing. an oil seal interposed between one side portion and the drive shaft and forming a seal chamber inside; and a drain hole formed within the pump casing and having one end open to the seal chamber. In the oil pump, a guide member separate from the pump casing is provided at a position forward of the opening at one end of the drain hole in the seal chamber in the rotational direction of the drive shaft, An oil pump characterized in that a dam member is provided between the part and the oil seal. 2. A pump casing rotatably housing an inner gear and an outer gear that mesh with each other; a drive shaft passing through substantially the center of the pump casing and connected to the inner gear; and the pump casing. an oil seal interposed between one side portion and the drive shaft and forming a seal chamber inside; and an oil seal formed at a connection point between the inner gear and the drive shaft, one end opening into the seal chamber. An oil pump having a drain hole, characterized in that a scraping member is provided at a position rearward in the rotational direction of the drive shaft with respect to an opening at one end of the drain hole at the end of the inner gear, the tip of which faces into the seal chamber. oil pump.