JPH11343849A - Cooling system for machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cool the oil and the engine cooling liquid in axle assemblies into appropriate temperature according to the operation mode of a machine by combining the cooling system of engine cooling liquid with the cooling system of oil in the axle assemblies capably of heat transmitting through a common heat exchanger. SOLUTION: A pipe line 26 circulating engine cooling liquid by operation of a pump 36 is provided in an engine cooling system 18 connected to an engine 12 through radiator hoses 22, 24, and a heat exchanger 30 is interposed on the way of the pipe line 26. First and second axle assemblies 14, 16 fitted to a machine are respectively provided with cooling systems 40, 58, they are constituted by providing pipe lines 44, 68 connected to the outlet ports 44, 62 of the lower parts of axle housings 38, 64. By circulating oil in the pipe lines 42, 68 by a pump 46 driven by the common engine 12, heat is exchanged with the engine cooling liquid through the heat exchanger 30, and both are cooled into appropriate temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to cooling systems, and more particularly to a cooling system that reduces the temperature of oil in an axle assembly or the temperature of engine coolant depending on the mode of operation of the machine. .

[0002]

BACKGROUND OF THE INVENTION In the operation of construction machines, it is common for the machine to be exposed to several different modes of operation. For example, in wheel loaders, this involves loading trucks, transporting luggage, and other more specialized operations.

[0003] For example, in the operation of transporting luggage, since the luggage is transported from one place to another, there is a large amount of machine movement in which the machine moves at a relatively high speed.

The application of brakes to the front and rear axles becomes very demanding because the braking action must achieve these high speeds before bringing the machine to a standstill. Applying a brake often heats the oil in the brake and the axle housing in which the brake is located to a high temperature.

[0005] If the work implement is used frequently without loading the truck or the machine is not running, there is no problem with the axle temperature since the brakes are used less often. However, in these cases, enhancing the engine cooling system is very effective to prevent the engine temperature from overheating.

In both of the above cases, heat is a by-product of different operations and is known to cause excessive wear and premature damage to many parts. Regarding overheating of the engine, several measures are known to be very effective.

[0007] These measures include increasing the capacity of the cooling system or adding refrigerant to the cooling system. With respect to overheating of axle assemblies, several methods are known for reducing heat. In some systems, oil is circulated through an air-to-oil cooler in the axle housing or coolant is circulated through the oil in the axle housing.

Although these systems have been found to be effective to some degree, they are often relatively complex and require many extra components to achieve the desired result. In addition, these systems are always operating and have very limited versatility.

It is therefore an object of the present invention to provide a machine cooling system which overcomes the above-mentioned problems of the prior art.

[0010]

DISCLOSURE OF THE INVENTION In one aspect of the present invention, a machine cooling system is provided. The cooling system includes an engine associated with the machine and a first cooling system adapted to cool a coolant circulating in the engine. A heat exchanger is arranged in the first cooling system, through which the engine coolant circulates.

[0011] At least one axle assembly is mounted on the machine and a second cooling system is provided for circulating oil through the axle assembly and a heat exchanger.

A pump adapted to selectively circulate oil in the second cooling system and drive engage the engine is disposed in the second cooling system. A clutch member is disposed between the pump and the engine to selectively engage the drive between the pump and the engine.

[0013] A first sensor for detecting engine temperature is adapted to engage the engine. When the temperature of the engine reaches a predetermined temperature, the first clutch is engaged so that the clutch is engaged.
The sensor is operatively connected to the clutch member.

[0014] A second sensor is adapted to engage the axle to detect axle temperature. The second sensor is operatively connected to the clutch member to engage the clutch when the temperature of the axle reaches a predetermined temperature.

In another aspect, the invention includes an engine, a pair of axles operatively connected to the engine to provide dynamic power to the machine, and a cooling system for reducing an operating temperature of the engine. Machine improvements are provided.

An improvement of this machine is that a heat exchanger located in the engine cooling system and oil is removed from one of the axle assemblies.
And a second cooling system circulated through a heat exchanger.

A third cooling system is provided for circulating the oil through another axle assembly and heat exchanger. Means are provided for selectively circulating oil through each axle and heat exchanger.

Means for sensing the temperature of the engine and axle assembly are also provided. The detecting means activates the circulating means in response to the temperature of either the engine or the axle reaching the predetermined temperature.

In the cooling system described above, a pair of sensors are associated with one or both axle assemblies and the engine coolant in the engine cooling system. When the temperature of the axle assembly or engine coolant reaches a predetermined temperature, a pump is activated to circulate fluid in the axle assembly through a heat exchanger located in the engine cooling system.

If the axle oil temperature is excessive, the engine coolant will pass through the heat exchanger to reduce the axle oil temperature. Conversely, if the temperature of the engine coolant is too high, cold axle oil circulates through the heat exchanger to reduce the temperature of the engine coolant. As such, the cooling system of the present invention provides the required cooling depending on the mode of operation of the machine.

[0021]

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings, a cooling system 10 for a machine is shown. The machine (not shown) includes an engine 12 drivingly connected to a pair of axle assemblies 14, 16 in a conventional manner not shown here.

The engine 12 has a conventional structure with an internal cooling system of a conventional design. Engine cooling system 18 includes a radiator 20 coupled to engine 12 by upper and lower radiator hoses 22 and 24 to provide cooling of the engine coolant in a conventional manner.

A line 26 through which engine coolant circulates is added to the engine cooling system, and line 26 is shown exiting the engine at an outlet port 28 and communicating fluid to a heat exchanger 30.

Another line 32 is connected between the heat exchanger 30 and the engine inlet port 34 to reintroduce the engine coolant into the engine cooling system.
The heat exchanger 30 includes a pump 36 driven by an engine.
So that the engine coolant circulates through lines 26 and 3
2 are arranged in communication.

The first axle assembly 14 is of a conventional construction having a differential assembly and a pair of axle shafts extending on opposite sides to drive a pair of wheels in a conventional manner.

A plurality of brake assemblies are connected to the axle shaft to provide braking of the machine in a conventional manner. All of these parts are housed in a common axle housing 38, the individual parts not being shown.

The first axle assembly 14 includes a second cooling system, indicated generally at 40. A second cooling system 40 extends from an outlet port 44 in the lower portion of the axle housing 38 to pump oil in the axle housing to a pump 46.
And a conduit 42 that communicates with the

Another line 48 communicates oil from the pump 46 to the heat exchanger 30. Oil from the heat exchanger 30 is supplied to the pipe 5
It is returned to the axle housing via 0 and 52 and enters the axle housing through a pair of inlet ports 54 and 56.

The second axle assembly 16 is substantially identical to the first axle assembly 14. Second axle assembly 16
Includes a third cooling system, indicated at 58.

The third cooling system 58 includes the axle housing 6
4 includes a line 60 that extends from an outlet port 62 located in the lower portion of 4 and communicates oil in axle housing 64 to pump 46.

Another line 66 communicates oil from the pump 46 to the heat exchanger 30. Oil from the heat exchanger 30 is supplied to the line 6
Returning to axle housing 64 via 8 and 70, 2
Axle housing 64 enters through two inlet ports 72 and 74.

The oil from both axle assemblies 14 and 16 is circulated by a common pump 46 via a common heat exchanger 30, but to eliminate the possibility of cross-contamination between the two systems, Note that the cooling systems are kept separate from each other.

The pump 46 is driven by an electric clutch member 76. The clutch member 76 is operated by one of a pair of sensors 78 and 80.

The first sensor 78 is connected to the engine 12 by a probe (not shown) located in the engine water jacket to detect the temperature of the engine coolant.
It is connected to the.

This probe is connected to a sensor 78 by a wire 82. When the engine coolant reaches a predetermined temperature, a signal is supplied from the sensor to the electric clutch 76 to drive the pump 46.

The second sensor 80 is also a probe-type sensor connected to the first axle 14 and detects the temperature of the oil in the axle assembly. This probe is connected to the sensor by a wire 84.

When the oil reaches a predetermined temperature, the second sensor 80 supplies a signal to the electric clutch 76 to drive the pump 46. Note that sensors 78 and 80 operate pump 46 in response to engine coolant or axle oil temperature and operate completely independently of one another.

[0038]

[Industrial Applicability] During operation of a construction machine such as a wheel loader, one of several operation modes is available.
It is common to operate the machine at one time.

In one common mode, the machine is used for tasks such as loading on trucks that use the engine excessively to operate a large number of work implements with little movement of the machine.

In this work mode, the temperature of the engine coolant rises. When the temperature of the engine coolant rises to a predetermined temperature, about 98 ° C. in this embodiment, the first
The sensor is activated and the electric clutch 76 is engaged to drive the pump 46 by the engine 12.

Thus, the pump 46 circulates the oil in the axle housings 38 and 64 through the heat exchanger 30. The oil in the axle housing is much colder than the engine coolant, since the machine is operating in a mode where there is not much movement and little braking.

Since the engine coolant and oil from the axle assembly are circulating in the same heat exchanger, the temperature of the engine coolant is reduced. Engine coolant temperature is about 95 ° C
, The first sensor 78 sends a signal to the clutch to cut off the drive between the engine and the pump.

In other modes of operation, such as, for example, transporting luggage, the machine is used to transport material from one location to another. During this movement, the machine is usually operated in the high speed range.

Upon reaching the destination, a large amount of brake capacity is required to slow down and stop the machine. Thereby, the oil in each axle housing 38 and 64 is heated by the brake assembly contained in the axle housing.

The temperature of the oil is a predetermined temperature, which is about 6 in this embodiment.
When the temperature reaches 5 ° C., the second sensor 80 is activated to engage the electric clutch 76. As described above, the electric clutch 76 transfers the drive of the engine 12 to the pump 46 and causes the oil in each axle assembly 14 and 16 to circulate through the heat exchanger 30.

In this mode of operation, the temperature of the oil in the axle housing is reduced as it circulates through the heat exchanger 30 because the temperature of the engine coolant is lower than the oil in the axle housing. When the temperature of the oil in the axle housing reaches about 57 ° C., the drive of the pump 46 will be disconnected by the clutch 76.

The cooling system of the present invention significantly reduces excessive wear and premature damage of many mechanical parts by providing additional cooling capacity to both the engine and the axle assembly. Furthermore, this additional cooling is achieved automatically depending on the operating conditions of the machine.

Other aspects, objects and advantages of the present invention can be obtained from a study of the drawings, the description and the appended claims.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a cooling system for a machine equipped with the principle of the present invention.

[Explanation of symbols]

 Reference Signs List 10 cooling system 12 engine 14, 16 axle assembly 18 engine cooling system 30 heat exchanger 36 pump 40 second cooling system 58 third cooling system 78, 80 sensor

Continued on the front page (72) Inventor Paul A. Dicke United States, 61614 Illinois, Peoria, E Reservoir Bullboard 2211 (72) Inventor Jeffrey A. Butler United States, 60506 Illinois, Aurora, Lula Drive 380

Claims (15)

[Claims] 1. A cooling system for a machine, comprising: an engine operatively connected to the machine; a first cooling system adapted to circulate engine coolant through the engine; A heat exchanger disposed in the first cooling system; at least one axle assembly attached to the machine; and a second adapted to circulate oil through the axle assembly and the heat exchanger.
A cooling system; a pump disposed in the second cooling system for drivingly engaging the engine to selectively circulate oil;
A clutch member disposed between the pump and the engine to selectively establish drive between the pump and the engine; adapted to engage the engine to detect a temperature of the engine; A first sensor operatively connected to the clutch member to engage the clutch when the temperature reaches a predetermined temperature; adapted to engage the axle assembly to detect a temperature of the axle assembly; A second sensor operatively connected to the clutch member to engage the clutch when the temperature of the machine reaches a predetermined temperature. 2. A system according to claim 1, wherein a second axle assembly is mounted on the machine, said second axle assembly being in communication with a third cooling system adapted to circulate oil therethrough. The cooling system of the described machine. 3. The machine according to claim 2, wherein the third cooling system includes a pump for circulating oil through the heat exchanger, the pump being in operative engagement with the engine and the clutch member. Cooling system. 4. The machine cooling system according to claim 4, wherein the oil in the third cooling system is circulated through the heat exchanger in a manner that does not communicate with the oil in the second cooling system. 5. The cooling system for a machine according to claim 1, wherein the heat exchanger is a heat exchanger between oil and water. 6. The cooling system for a machine according to claim 5, wherein a radiator is disposed in the first cooling system, and the radiator has a function of exchanging heat between air and water. . 7. The machine cooling system of claim 1, wherein the axle assembly includes a plurality of brake elements arranged in communication with the second cooling system. 8. The system according to claim 1, wherein the first sensor detects a temperature of the engine coolant in the first cooling system, and the second sensor detects a temperature of the oil in the second cooling system. Machine cooling system. 9. A machine having an engine, a pair of axle assemblies drivingly coupled to the engine to provide dynamic power to the machine, and a cooling system for reducing an operating temperature of the engine, wherein the machine includes an engine cooling system. A second cooling system for circulating oil through one of the axle assemblies and the heat exchanger; a third cooling system for circulating oil through the other of the axle assemblies and the heat exchanger; and through each axle assembly and heat exchanger. Means for selectively circulating oil; and means for detecting the temperature of the engine or axle assembly and activating the circulation means when one of the engine or the axle assembly reaches a predetermined temperature. Machine improvement. 10. The improvement of the machine of claim 9, wherein the second and second cooling systems are separate systems that do not communicate with each other. 11. The improvement of the machine of claim 9, wherein the circulation means further comprises a pump operatively connected to the engine and circulating oil through each axle assembly. 12. The improvement according to claim 11, wherein a clutch member is disposed between the pump and the engine for selectively engaging the pump with the engine. 13. The detecting means includes a first sensor adapted to engage the engine to detect a temperature of the engine, wherein the first sensor selectively engages a clutch member to engage the engine. 13. The improvement of the machine of claim 12, wherein a drive engagement between the pump and the engine is provided as the temperature reaches a predetermined temperature. 14. The detection means includes a second sensor adapted to engage at least one axle assembly to detect a temperature of the axle assembly, wherein the second sensor is adapted to engage the at least one axle assembly.
13. The machine of claim 12, wherein the sensor is operatively engaged with the clutch member to provide drive engagement between the pump and the engine in response to the axle assembly reaching a predetermined temperature. Improvement. 15. The detecting means includes: a first sensor engaged with a clutch member, wherein the pump circulates oil in the axle assembly through the heat exchanger to reduce the temperature of the engine coolant in the engine cooling system. A first state and a second state wherein the second sensor is engaged with the clutch member and the pump operates in a second state in which oil in the axle assembly is circulated through the heat exchanger to reduce the temperature of the oil in the axle assembly. 15. The improvement of the machine of claim 14, wherein