JPH04101747A - Jet lubrication device - Google Patents

Abstract

PURPOSE:To prevent a pump from wearing, by connecting a feed oil pass from a lubrication pump to a lubricating port, connecting a drain oil pass to a scavenge pump to a drain oil port, connecting a leakage oil pass to a leakage oil pump to a leakage oil port, branching a branch pass from the feed oil pass, and connecting this branch pass to the inlet side of the leakage oil suction pump. CONSTITUTION:Bearings 2, 3 are lubricated and cooled by the lubrication oil fed to feed oil ports 6, 7 from a feed oil pump 19, and the smooth and high speed rotation of a main shaft 1 is secured. This lubrication oil is returned to a reservoir 32 with its being sucked to drain oil pumps 26, 28 from drain oil ports 9, 11. Also the lubrication oil leaked from between the main shaft 1 and housing 5 is sucked to a leak oil suction pump 30 from oil leakage ports 12, 17, and this is also returned to the reservoir 32, so the pollution of the peripheral side with the lubrication oil being leaked to the housing 5 external part is prevented. On the other hand, the lubrication oil discharged from a feed oil pump 19 is fed to a leakage oil suction pump 30 via a branch pass 31 at its one part, contributing to the lubrication of the leakage oil suction pump 30 even in the case of the leakage oil quantity being small. The early wear of the leakage oil suction pump 30 can thus be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a jet lubrication device for a spindle that is used in a machine tool such as a high-speed machining center and is jet-lubricated.

[Conventional technology]

As a conventional jet lubrication device, for example,
There is one described in Japanese Patent No. 42841. This conventional device has a housing arranged around the outer circumference of the main shaft via a bearing, and the housing has an oil supply port to the bearing, an oil drain port from the bearing, and an oil leak port to drain oil leaked from the bearing. The oil supply port is connected to an oil supply path from an oil supply pump, the oil drain port is connected to an oil drain path to an oil drain pump, and the oil leak port is connected to an oil leakage suction pump. Connect the oil leakage path.

According to this conventional technology, the bearing is lubricated and cooled with the lubricating oil supplied from the oil pump to the oil supply port, and this lubricant is sucked into the oil drain pump from the oil drain port and returned to the reservoir. Also, lubricating oil leaking from between the spindle and the housing is sucked into the oil leakage suction pump through the oil leakage port and returned to the reservoir, so there is no chance of lubricating oil leaking outside the housing and contaminating the surrounding area. is prevented.

[Problem to be solved by the invention]

However, according to the conventional jet lubrication device,
The better the oil seal function is, the less oil leaks, and therefore the oil leakage suction pump sucks in a large amount of air, increasing the amount of time it idles. In this case, the oil leakage suction pump tends to lack lubrication, resulting in a problem that the pump wears out.

Therefore, this invention was made by focusing on the above-mentioned problems of the prior art, and even if the amount of oil leakage is small, the necessary amount of lubricating oil is supplied to the oil leakage suction pump to prevent wear of the oil leakage suction pump. The purpose is to prevent.

[Means to solve the problem]

The jet lubrication device of the present invention has a housing arranged around the outer circumference of the main shaft via a bearing, and the housing has an oil supply port to the bearing, an oil drain port from the bearing, and an oil leakage port for draining oil leaked from the bearing. An oil supply path from an oil supply pump is connected to the oil supply port, an oil drainage path to an oil drainage pump is connected to the oil drain port, and an oil leakage suction pump is connected to the oil leakage port. A branch path is branched from the oil supply path, and this branch path is connected to the inlet side of the oil leakage suction pump.

Instead of branching off from the oil supply path, the inlet side of the oil leakage suction pump may be connected to a reservoir to supply a small amount of lubricating oil.

[Effect]

The bearing is lubricated and cooled with lubricating oil supplied from the oil supply pump to the oil supply port, ensuring smooth high-speed rotation of the main shaft. This lubricating oil is sucked into the oil drain pump through the oil drain port and returned to the reservoir. In addition, lubricating oil leaking from between the main shaft and the housing is sucked into the oil leakage suction pump through the oil leakage port and returned to the reservoir, preventing lubricating oil from leaking outside the housing and contaminating the surrounding area. To prevent. On the other hand, part of the lubricating oil discharged from the oil supply pump is supplied to the oil leakage suction pump through a branch path, and even if the amount of oil leakage is small, it contributes to the lubrication of the oil leakage suction pump. This prevents premature wear of the leakage suction pump.

If the inlet side of the oil leakage suction pump is connected to the reservoir instead of the branch path, the oil leakage suction pump is directly supplied with oil from the reservoir for lubrication. Examples of this direct lubricating means include means using a small pump, and means using the negative pressure of an oil leakage suction pump to suck lubricating oil from a reservoir.

〔Example〕

FIG. 1 shows a first embodiment of a vertical jet lubrication device, which is used as a main shaft of a high-speed machining center or the like. Here, the main shaft 1 is installed vertically with the direction of arrow A facing upward, and a plurality of bearings 2 and 3 are fitted around its outer periphery with their inner rings fixed. 3,
A spacer 24 is interposed between the lower bearing 2 and the upper bearing 3, and a spacer 23 is also interposed between the lower bearing 2 and the upper bearing 3. Each bearing 2
A housing 5 is externally fitted and fixed to the outer ring of the angle 3, and the main shaft 1 is surrounded by the housing 5.

The housing 5 has two jet lubricating oil fill ports 6,
7 is opened, and the upper oil supply port 6 supplies lubricating oil to the upper bearing 2 via a lubricating oil passage 6a that is continuous with the oil supply port 6, and the lower oil supply port 6 supplies lubricant oil that is continuous with this. The lower bearing 3 is lubricated via the oil passage 7a.

The lubricating oil that has lubricated the bearing 2 is passed through the passage 8 to the oil filler port 6.
The lubricating oil that has reached the oil drain port 9 on the lower side and that has lubricated the bearing 3 reaches the oil drain port 11 that is on the lower side of the oil supply lower side via the passageway 0. Further, oil leak ports 17 are provided at the upper and lower ends of the housing 5 to drain oil leakage.
12 are provided.

Members 14, 15, and 16, both of which form part of the housing 5, are fitted onto the outer periphery of the lower end of the main shaft 1. An oil pocket 13 is formed below the oil drain port 11 in which oil that has passed through the labyrinth 18 formed between the members 15 and 16 accumulates, and the oil leak port 12 opens into this oil pocket 13.

Said oil supply ports 6, 7, oil drain ports 9, 11, oil leak ports 17, 12
The following oil passages are connected to:

That is, the oil supply ports 6 and 7 are respectively connected to the distributor 21 connected to the tip of the oil supply path 20 from the outlet side of the oil supply pump 19, and lubricating oil is supplied to each at a predetermined ratio, and one drained oil The inlet side of a drain oil pump 26 is connected to the port 9 via a drain oil passage 25, and the inlet side of a drain oil pump 28 is connected to the other oil drain port 11 via a drain oil passage 27. Also, oil leak port 1
7.12 is connected to the inlet side of an oil leak suction pump 30 via an oil leak path 29, and a branch path 31 branched from the oil supply path 20 is connected to the oil leak path 29.

The oil drain pump 26 has a higher oil supply capacity than the oil supply pump 19.
．． 28 has a suction capacity commensurate with the amount of oil distributed by the distributor 21, and the oil leakage suction pump 3° only needs to have the suction capacity for leakage oil, so its suction capacity is compared to the oil drain pump 26 and 28. And it is set even lower. Therefore, the suction amount of the oil leakage suction pump 30 is much lower than the amount of oil supplied by the oil supply pump 19. In this embodiment, trochoid pumps are used as the pumps 26, 28, and 30. 32 is a reservoir, and 33 and 34 are flow rate regulating valves, each of which is a throttle valve or a variable throttle valve.

The lubricating oil supplied from the oil supply pump 19 is distributed by the distributor 21 through the oil supply path 20 and enters the housing 5 through the oil supply ports 6 and 7, and is used to lubricate and cool the bearing 2.3 as described above. The oil reaches the drain ports 9 and 11 while passing through the oil drain passage 25.27 by the suction force of the oil drain pump 26.28, and is sucked into the oil drain pump 26.2B, and is further drawn into the reservoir on the outlet side of these oil drains. It will be returned to 32.

Further, the leaked oil is sucked into the oil leak suction pump 30 through the oil leak passage 29 through the oil leak ports 17 and 12, and returns to the reservoir 32. Here, since a branch path 31 branching from the oil supply path 20 is connected to the inlet side of the oil leakage suction pump 30, this pump 30 has the discharge amount of the oil supply pump 19 and the flow rate regulating valve 3.
A predetermined amount of lubricating oil determined in relation to the value set by 3.34 is constantly supplied, and the oil leak port 1
7. Even if there is no or small amount of oil leaking from 12,
The minimum amount of oil sucked into the oil leakage suction pump 30 is guaranteed. For this reason, there is no risk of insufficient lubrication or wear of the pump 3o due to an insufficient amount of oil in the leakage suction pump 30.

In addition, in this embodiment, the branch path 3 is separated from the oil supply path 20.
1, the lubricating oil is constantly supplied to the oil leakage suction pump 30 through the valves 33 and 34, but
Alternatively, a conventional valve mechanism in the hydraulic circuit may be used to cause the lubricating oil to pass through the branch passage 31 at predetermined time intervals necessary for lubrication of the pump 30.

Further, in this embodiment, an example in which the present invention is applied to a vertical jet lubrication device has been described, but the present invention can also be applied to a horizontal jet lubrication device in which the main axis l is horizontal.

FIG. 2 shows a second embodiment, in which the leakage suction pump 30 is directly supplied with oil from the reservoir 32. In Figure 2, the main shaft 1, housing 5, etc. are the same as in Figure 1, so they are omitted for each pump 19.26.28.30.
and shows the reservoir 32 part.

Here, the branch passage 31 and the flow rate regulating valves 33, 34 of the first embodiment are not used, but instead a sub-lubrication passage 36 having a small sub-oil pump 37 is used. That is, the other end of the sub-oil supply passage 36, which has one end facing into the reservoir 32, is connected to the oil leak passage 29 of the first embodiment, and the oil leak port 12 and the reservoir are connected to the inlet side of the oil leak suction pump 30. 32 are connected. The auxiliary oil supply pump 37 of the auxiliary oil supply passage 36 is
It is only necessary to have the ability to supply a small amount of lubricating oil necessary for lubrication of the oil leakage suction pump 30 from the reservoir 32 to the oil leakage path 29.

FIG. 3 shows a third embodiment, in which a throttle valve 35 is interposed in the auxiliary oil supply passage 36 in place of the auxiliary oil supply pump 37 of the second embodiment. This is achieved by interposing a throttle valve 35 with a fixed or variable opening area so that the pump 30 can reach the reservoir 32.
This prevents suction of only the lubricating oil from the oil leak port 12 and prioritizes the suction of the leaked oil from the oil leak port 12, and the amount of leaked oil is insufficient and the negative pressure on the oil leak suction pump 30 person side exceeds a predetermined value. It is designed to refuel from the reservoir 32 only occasionally. This third embodiment is applicable when the degree of pressure reduction in the oil pocket 13 and the labyrinth 18 shown in FIG. This is particularly effective.

According to these 2.3 embodiments, the entire amount of oil supplied from the oil supply pump 19 is constantly supplied to the bearings 2.3, so that the lubrication and cooling functions of these bearings 2.3 are not degraded. Moreover, there is no need to control the amount of oil to the branch path.

The power source of the sub-lubricating pump 37 of the second embodiment is connected to a timer, and the throttle valve 35 of the third embodiment is made variable so that the lubricating oil is supplied at predetermined time intervals necessary for lubricating the pump 30. Alternatively, a temperature sensor may be installed in the pump 30, and when the temperature reaches a predetermined temperature or higher, the sub-lubrication pump 37 is activated and the throttle is turned on. A control circuit may be provided to open the valve 35. The other configurations and operations in the 2.3 embodiment are the same as those in the first embodiment.

〔Effect of the invention〕

As explained above, in the invention of the first claim, a housing is disposed on the outer periphery of the main shaft via a bearing, and the housing has an oil supply port for the bearing, an oil drain port from the bearing, and a housing for the bearing. an oil leakage port for discharging oil leakage from the oil supply port, an oil supply path from an oil supply pump is connected to the oil supply port, an oil drainage path to the oil drainage pump is connected to the oil drain port, and an oil drainage path to the oil drainage pump is connected to the oil supply port; An oil leak path to the oil leak suction pump is connected to the oil leak port, and a branch path is branched from the oil supply path, and this branch path is connected to the inlet side of the oil leak suction pump, so that no leakage occurs from the oil supply path. It was decided that the minimum amount of oil required for the oil suction pump would be supplied directly via a branch line. Therefore, even if the amount of oil leaking from the jet lubrication spindle is small or not at all, the oil leakage suction pump can be lubricated, and adverse effects such as wear can be prevented.

In addition, in the invention of the second claim, instead of the branch path of the invention of the first claim, the inlet side of the oil leakage suction pump is connected to the reservoir, so that the minimum necessary distance from the reservoir to the oil leakage suction pump is It is possible to directly supply a limited amount of oil, and therefore the first
Similar to the claimed invention, even if the amount of oil leaked from the jet lubrication spindle is small or not at all, the oil leakage suction pump can be lubricated and adverse effects such as wear can be prevented. be.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the first embodiment, FIG. 2 is an explanatory diagram of the main part of the second embodiment, and FIG. 3 is an explanatory diagram of the main part of the third embodiment. 1... Main shaft, 2, 3... Bearing, 5... Housing, 6.7... Oil filler port, 9.11... Oil drain port, 12.
17...Oil leak port, 19...Oil supply pump, 20...
Oil supply path, 25.27... Oil drain path, 26.28... Oil drain pump, 29... Oil leak path, 30... Oil leak suction pump, 31... Branch path, 32...・Reservoir, 35・Valve, 36... Refueling subway. aperture

Claims (2)

[Claims] (1) A housing is disposed on the outer periphery of the main shaft via a bearing, and the housing includes an oil supply port to the bearing, an oil drain port from the bearing, and an oil leak port for draining oil leaked from the bearing, A fuel supply path from a fuel pump is connected to the fuel supply port, and
The oil drain port is connected to an oil drain path to an oil drain pump, the oil leak port is further connected to an oil leak path to an oil leak suction pump, and a branch path is branched from the oil supply path, A jet lubrication device characterized in that this branch path is connected to an inlet side of the oil leakage suction pump. (2) A housing is disposed on the outer periphery of the main shaft via a bearing, and the housing includes an oil supply port to the bearing, an oil drain port from the bearing, and an oil leak port for draining oil leaked from the bearing, A fuel supply path from a fuel pump is connected to the fuel supply port, and
An oil drain path to an oil drain pump is connected to the oil drain port, and an oil leak path to an oil leak suction pump is connected to the oil leak port, and the inlet side of the oil leak suction pump is connected to a reservoir. A jet lubrication device characterized by being connected to.