JP2006038133A - Warning control device of construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a warning control device of a construction machine capable of preventing inconvenience caused by intrusion of foreign matter into a seal storage chamber. <P>SOLUTION: This warning control device has a speed reducer 26 having a housing 28, a casing 32 rotatably supported via a bearing on an outer peripheral surface of the housing and storing a speed reduction gear mechanism in an inside speed reduction gear chamber, the annular seal storage chamber 74 adjacent to the speed reduction gear chamber and an annular floating seal 76 arranged in the seal storage chamber and liquidtightly sealing the seal storage chamber to an external part, a temperature detecting means 66 arranged in the seal storage chamber and detecting the temperature of lubricating oil in the seal storage chamber, a controller 67 for outputting a warning signal when this discriminating result is determined as abnormal by discriminating a sliding calorific value by the floating seal from a detecting result detected by the temperature detecting means, and a warning means 94 for generating a warning on the basis of the warning signal. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a warning control device for a construction machine used for various construction work such as a hydraulic excavator and a crawler carrier.

This type of construction machine, such as a hydraulic excavator, includes a crawler-type lower traveling body, and the lower traveling body travels by transmitting an output of a traveling motor by hydraulic pressure to a sprocket of the crawler via a reduction gear.
More specifically, the speed reducer includes a housing that surrounds the traveling motor, and a casing that is rotatably supported on the outer peripheral surface of the housing via a bearing. The casing and the housing cooperate with each other to receive a seal. Forming a chamber. A floating seal is disposed in the seal housing chamber, and the floating seal functions as a seal member for internal lubricating oil.

In view of the possibility that foreign matter such as earth and sand can enter from the outside through the gap between the housing and the casing, a technique in which a separate seal member is disposed between the gap and the floating seal is disclosed. (Patent Document 1).
Japanese Utility Model Publication No. 55-105661

By the way, the hydraulic excavator frequently travels on rough roads such as rough terrain, mud and rock soil, and the lower traveling body is required to proceed even when buried in earth and sand. That is, foreign matters such as earth and sand are constantly pushed toward the lower traveling body, and a large earth pressure is generated in the lower traveling body from the outside toward the seal housing chamber.
Here, depending on the working environment of the excavator, the excavator may be required to continuously run for a long time. The earth pressure during continuous running has a greater pressure and continuously acts toward the seal housing chamber. Accordingly, simply providing a seal member as in Patent Document 1 does not sufficiently prevent foreign matter from entering the seal accommodation chamber, and no special consideration is given to the case where foreign matter enters the seal accommodation chamber. .

  During the continuous running, once the foreign matter enters the seal housing chamber from the outside, the floating seal is pressed by the foreign matter and generates heat. This causes breakage of the floating seal and makes it difficult to maintain the sealing performance of the lubricating oil for a long period of time. In addition, if the operator of the excavator continues the traveling operation without noticing the leakage of the lubricating oil, the reduction gear can be damaged.

Furthermore, the heat generated by the floating seal overheats the seal housing chamber, which causes a problem that the heat balance of the speed reducer deteriorates. That is, the sliding heat generated by the sliding is trapped in the seal housing chamber, which causes the lubricating oil in the reduction gear chamber to deteriorate early and shorten the life of the gears, bearings, and the like in the reduction gear chamber.
The present invention has been made in view of such a problem, and an object of the present invention is to provide a warning control device for a construction machine that can prevent problems associated with the entry of foreign matter into a seal accommodation chamber.

  To achieve the above object, a warning control device for a construction machine according to the present invention (Claim 1) is a construction machine including a travel motor and a speed reducer that transmits the output of the travel motor to a travel rotator, A housing that surrounds the travel motor, a casing that is rotatably supported on the outer peripheral surface of the housing via a bearing, and that accommodates the reduction gear mechanism in the internal reduction gear chamber, and allows the casing to rotate between the casing and the housing. And a ring-shaped seal housing chamber adjacent to the reduction gear chamber via a bearing, and a ring-shaped floating seal that is disposed in the seal chamber and seals the seal chamber in a liquid-tight manner with respect to the outside. And a temperature detecting means for detecting the temperature of the lubricating oil in the seal containing chamber, and a detection result detected by the temperature detecting means to the floating seal. That the sliding heat generation amount determined, a controller for outputting a warning signal when the result of this determination is determined to be abnormal on the basis of the warning signal, is characterized by comprising a warning means for generating a warning.

Further, the invention according to claim 2 is characterized in that the warning means generates a warning for prompting a deceleration operation of the vehicle speed.
Further, the invention according to claim 3 is characterized in that the warning means outputs a signal for forcibly decelerating the vehicle speed to the traveling motor as a warning.

The present invention focuses on preventing problems caused by sliding heat even when sliding heat is generated in the floating seal as foreign matter enters the seal housing chamber.
According to the warning control device for a construction machine of the first aspect of the present invention, the amount of sliding heat generated by the floating seal is determined, and if the determination result is determined to be abnormally high temperature, a warning is given via the controller. A warning is issued from the means, and alerts the operator of the construction machine about the heat generation state. In other words, even if foreign matter such as earth and sand enters from the outside into the seal housing chamber due to earth pressure, and the sliding heat generation amount due to the floating seal becomes abnormally large, the temperature rise of the lubricating oil in the seal housing chamber is suppressed by the warning signal. The

As a result, it is possible to prevent the floating seal from being damaged due to continuous running of the construction machine over a long period of time. In addition, the sealing performance of the lubricating oil by the floating seal can be stably maintained over a long period of time, the speed reducer can be prevented from being damaged due to the leakage of the lubricating oil, the inability to run the vehicle body can be avoided, and the environmental pollution It also contributes to prevention.
Furthermore, the heat balance of the entire reduction gear is also improved, the lubricating oil in the reduction gear chamber does not deteriorate quickly, and the life of the gears, bearings, etc. of the reduction gear mechanism due to this heat deterioration is not shortened.

  According to the second aspect of the present invention, a warning that prompts a deceleration operation of the vehicle speed is issued from the warning means when it is determined that the amount of sliding heat generated by the floating seal is abnormally high. Therefore, the operator is made aware of the heat generation state, and is decelerated by the operator's own deceleration operation. As a result, it is possible to prevent problems associated with the sliding heat of the floating seal while continuing operations and running operations.

  Further, according to the third aspect of the present invention, when it is determined that the amount of sliding heat generated by the floating seal is abnormally high, a deceleration command is issued from the warning means to force the deceleration, in other words, the vehicle speed. Automatic regulation takes place. As a result, a human error is avoided, and problems associated with the sliding heat of the floating seal can be prevented more reliably.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a hydraulic excavator as a construction machine. The hydraulic excavator is provided with a crawler-type lower traveling body 2 and an upper revolving body 4 provided on the lower traveling body 2 so as to be able to swivel. 10 etc. are mounted. The working machine body 10 is configured such that an arm 14 is rotatably attached to the tip of the hoisting boom 12 and a rotatable bucket 16 is attached to the tip of the arm 14.

The lower traveling body 2 includes a traveling device 20 for traveling the crawler 18, and details of the traveling device 20 are shown in FIG. 2.
The traveling device 20 includes a traveling motor 22 using hydraulic pressure, and a reduction device 26 that transmits the output of the traveling motor 22 to a sprocket (traveling rotator) 24 of the crawler 18.
The speed reducer 26 has a cylindrical housing 28 that surrounds the output shaft side of the travel motor 22. The housing 28 has a mounting flange 30 at one end, and is connected to the side frame of the lower traveling body 2 via the mounting flange 30.

  The reduction gear 26 also has a cylindrical casing 32, and an end wall 33 of the casing 32 is rotatably supported on the other end of the housing 28 via a double row tapered roller bearing (bearing) 34. Yes. More specifically, the casing 32 includes a drive cylinder 36 having an end wall 33, a hollow cylinder 38, and a lid 40 from the housing 28 side, which are connected to each other to form a reduction gear chamber 42 in the casing 32. The sprocket 24 described above is attached to the drive cylinder 36.

  A reduction gear mechanism 44 is accommodated in the reduction gear chamber 42. For example, the reduction gear mechanism 44 includes a two-stage planetary gear mechanism. Specifically, the reduction gear mechanism 44 has an input shaft 46, one end of which is connected to the output shaft 23 of the travel motor 22. A sun gear 48 of the first stage planetary gear mechanism is integrally formed at the other end of the input shaft 46, and the sun gear 48 is formed on the inner peripheral surface of the hollow cylinder 38 via a plurality of planet gears 50. The teeth 52 are engaged with each other. The planetary gear 50 is supported by a carrier 56 via a pin 54, and the carrier 56 rotates integrally with the sun gear 58 of the second stage planetary gear mechanism. The sun gear 58 is rotatably supported by the input shaft 46 and meshes with the inner teeth 52 of the hollow cylinder 38 via a plurality of planetary gears 60, and the planetary gear 60 is supported by a carrier 64 via pins 62, and this carrier 64 is supported by the housing 28 so as not to rotate.

Accordingly, the output of the traveling motor 22 is transmitted to the hollow cylinder 38, that is, the casing 32 through the reduction gear mechanism 44 described above, and as a result, the sprocket 24 is rotated together with the casing 32.
On the other hand, an annular fixing sleeve 68 projects integrally from the mounting flange 30 of the housing 28 toward the drive cylinder 36 of the casing 32. On the other hand, the rotating sleeve 70 protrudes integrally from the drive cylinder 36 toward the mounting flange 30. The fixed and rotating sleeves 68 and 70 are engaged with each other with their tips allowed to rotate the rotating sleeve 70, and cooperate with the outer peripheral surface of the housing 28 and the end wall 33 of the casing 32 to receive an annular seal. A chamber 74 is formed.

  The seal accommodation chamber 74 is adjacent to the reduction gear chamber 42 via the tapered roller bearing 34, and the lubricating oil in the reduction gear chamber 42 can flow into the seal accommodation chamber 74 through the tapered roller bearing 34. Therefore, an annular floating seal 76 is accommodated in the seal accommodating chamber 74, and the floating seal 76 prevents leakage of the lubricating oil from the seal accommodating chamber 74 to the outside and seals the lubricating oil.

  The floating seal 76 includes a pair of seal rings 78 and an O-ring 80 that elastically supports the seal rings 78. More specifically, the pair of seal rings 78 are juxtaposed in the axial direction of the housing 28 and come into contact with each other, and these contact surfaces are formed as slidable contact surfaces 82. The pair of seal rings 78 are formed with male taper surfaces opposite to each other on their outer peripheral surfaces. On the other hand, the inner peripheral surfaces of the fixed and rotating sleeves 68 and 70 are respectively formed as female tapered surfaces corresponding to the male tapered surfaces of the seal ring 78, and an O-ring 80 is disposed between both the tapered surfaces of the male and female. Yes. These O-rings 80 seal between the corresponding seal rings 78 and the fixed or rotating sleeves 68, 70, while pressing the pair of seal rings 78 together to ensure that the sliding contact surfaces 82 of the seal rings 78 are in close contact with each other. .

Therefore, when the casing 32 is rotated, the seal ring 78 on the rotary sleeve 70 side comes into sliding contact with the seal ring 78 on the fixed sleeve 68 side, and these seal rings 78 cooperate with the O-ring 80 to form the seal housing chamber 74. Is sealed against the outside.
Incidentally, an oil temperature sensor (temperature detection means) 66 is disposed at an appropriate position of the seal housing chamber 74 that houses the floating seal 76. The oil temperature sensor 66 detects the temperature of the lubricating oil flowing into the seal housing chamber 74 and transmits a detection signal to a warning controller (controller) 67. The warning controller 67 includes a central processing unit (CPU), a memory such as a ROM and a RAM, and a microcomputer including various peripheral devices such as a warning lamp driver. The floating seal 76 is obtained from the detection result of the oil temperature sensor 66. The amount of heat generated by sliding is determined. The warning controller 67 then outputs a warning signal to the warning lamp (warning means) 94 at the time of abnormally high temperature on the monitor panel 84 based on the determination result. The monitor panel 84 is mounted in the cab 6 and is disposed at a position that can be easily confirmed by the operator of the excavator (FIG. 1).

Details of the monitor panel 84 are shown in FIG.
Various displays are visually recognized on the monitor panel 84. More specifically, the meter 86 indicates the water temperature and the fuel amount, the liquid crystal display unit 88 that displays the engine rotation speed and the hydraulic oil temperature, the work display unit 90 that displays the excavation work mode, the water temperature, the fuel amount, and the like. Warning lamps 92 for displaying various warnings are arranged at appropriate positions on the panel. Further, in the present embodiment, a warning lamp 94 at an abnormally high temperature is arranged on the right side of the warning lamp 92, and is formed with a larger display than each display of the warning lamp 92.

  In the warning routine in the present embodiment, first, the oil temperature sensor 66 detects the temperature of the lubricating oil in the seal housing chamber 74, in other words, the temperature of the floating seal 76 or the vicinity of the floating seal 76. Next, the warning controller 67 determines the amount of heat generated by sliding with the floating seal 76 from the detection result of the oil temperature sensor 66. When it is determined that the temperature of the lubricating oil in the seal housing chamber 74 exceeds a predetermined threshold value and has reached an abnormally high temperature, a warning signal is output to the warning lamp 94 to warn the operator.

Specifically, first, the warning lamp 94 is turned on in response to a warning signal from the warning controller 67. The meaning of this lighting is described in the instruction manual of the hydraulic excavator to be recognized by the operator, for example, that the vehicle speed is decelerated from high speed to medium speed. Arouse.
Next, it blinks when the running operation is continued with the abnormal temperature exceeding a predetermined set time or a predetermined set number of times. That is, the display of the warning lamp 94 changes from lighting to blinking.

  The meaning of this flashing is also described in the instruction manual that, for example, the vehicle speed is decelerated from a medium speed to a low speed, the service is promptly contacted, and maintenance of the speed reduction device 26 is required. 94 flashes for further attention. The service side that has received the communication checks the reduction gear 26 and the floating seal 76, and if there is a malfunction, the floating seal 76 is replaced.

  As described above, in the present embodiment, the amount of sliding heat generated by the floating seal 76 is determined from the oil temperature of the lubricating oil in the seal housing chamber 74. If the determination result is determined to be abnormally high temperature, a warning by lighting or blinking is issued from the warning lamp 94 via the warning controller 67 to alert the operator about the heat generation state. Therefore, even if foreign matter such as earth and sand enters from the outside into the seal housing chamber 74 due to earth pressure and the amount of sliding heat generated by the floating seal 76 becomes abnormally large, a warning prompting the vehicle speed reduction operation from the warning lamp 94 Is decelerated by the operator's own decelerating operation, and the temperature rise of the lubricating oil in the seal housing chamber 74 is suppressed.

As a result, the work and the traveling operation are not immediately interrupted, and the opportunity to perform maintenance of the reduction gear 26 before the floating seal 76 is damaged by the alerting by the warning is obtained. This can prevent the floating seal 76 from being damaged.
Further, the sealing performance of the lubricating oil by the floating seal 76 can be stably maintained over a long period of time. Therefore, the speed reduction device 26 is prevented from being damaged due to leakage of the lubricating oil, the vehicle cannot run and the environmental pollution can be prevented.

Furthermore, the heat balance of the entire reduction gear 26 is also improved, and the lubricating oil in the reduction gear chamber 42 is unlikely to be thermally deteriorated at an early stage. Further, shortening of the lifespan of the various gears 48, 50, 52, 60, the tapered roller bearing 34, etc. of the reduction gear mechanism 44 due to this thermal deterioration is also avoided.
FIG. 4 shows another embodiment of the present invention. This embodiment has the same configuration as that of the above embodiment except for the specific contents of the warning. Therefore, this warning content will be described in detail.

The warning forcibly decelerates the vehicle speed while suppressing the supply flow rate of hydraulic oil to the traveling motor 22. More specifically, the traveling motor 22 is connected to a variable displacement main hydraulic pump 98 via a traveling control valve 100 as shown in the hydraulic circuit of FIG.
The traveling control valve 100 is a four-port three-position switching valve, which is operated by selecting either a spring or a pilot pressure system, and switches the flow direction of hydraulic oil. The pilot pressure oil pressure P ₀ is guided from the pilot pump 106 and is supplied to the travel control valve 100 in accordance with the operation position of the travel lever 96 interlocked with the left and right crawlers 18. The travel lever 96 is installed in the cab 6 (FIG. 1).

The main hydraulic pump 98 supplies pressure oil to the traveling motor 22, and the pressure is controlled by the relief valve 102 to protect the circuit. That is, when the discharge pressure of the main hydraulic pump 98 becomes higher than the pressure set by the spring 102A provided in the relief valve 102, the pressure oil discharged from the main hydraulic pump 98 is returned to the tank.
On the other hand, in the present embodiment, a main hydraulic control device (warning means) 104 is provided for the hydraulic circuit. The main hydraulic pressure control device 104 includes an electromagnetic pressure reducing valve 108 and a regulator 110, and the pressure reducing valve 108 is connected to a pilot pump 106.

  The pressure reducing valve 108 is driven based on a warning signal from the warning controller 67, and the pressure oil from the pilot pump 106 is controlled to an arbitrary pressure P and supplied to the regulator 110. Note that the pilot pressure on the OUT side is guided to the pressure reducing valve 108, and when the pilot pressure becomes a value equal to or higher than a predetermined pressure, the gap between IN and OUT is blocked and the supply to the regulator 110 is shut off. .

FIG. 5 is a flowchart of the supply flow rate control of the travel motor 22 by the main hydraulic control device 104 in the warning routine according to the present embodiment.
In step S501 in FIG, oil temperature t of the lubricating oil in the seal accommodating chamber 74 is read in the oil temperature sensor 66, in step S502, the oil temperature t at warning controller 67 exceeds a predetermined threshold value t ₀ It is determined whether or not it exists. If it is determined that the oil temperature t reaches an abnormally high temperature and the amount of sliding heat generated by the floating seal 76 is abnormal, that is, if YES, the routine proceeds to step S503, where the current i (= i ₁ ) is output and the process proceeds to step S504.

In step S504, the pressure P ₀ from the pilot pump 106 is changed to the pressure P (e.g., P _0/2) under reduced pressure valve 108, in step S505, the maximum tilt angle of the main hydraulic pump 98 via a regulator 110 .theta.max Suppress. Due to the suppressed maximum tilt angle θmax, the maximum supply flow rate Qmax discharged from the main hydraulic pump 98 is limited, the maximum flow rate supplied to the travel motor 22 via the travel control valve 100 is reduced, and the vehicle speed is reduced. For example, it is automatically set from medium speed to low speed.

In the present embodiment, when the oil temperature t exceeds the predetermined threshold value t ₀ in step S502, the warning controller 67 also outputs a warning signal to the monitor panel 84 and turns on the warning lamp 94 when the temperature is abnormally high. To warn the operator.
On the other hand, when the oil temperature t does not exceed the predetermined threshold t ₀ in step S502, the process proceeds to step S507, and the warning controller 67 outputs the current i (= i ₀ ) to the pressure reducing valve 108.

Next, in step S508, the pressure P of the pressure reducing valve 108 is maintained at the pressure P ₀ from the pilot pump 106, and in step S509, the maximum tilt angle θmax of the main hydraulic pump 98 is maintained. Thereby, the maximum supply flow rate Qmax to the traveling motor 22 is maintained, and the series of routines is terminated without issuing a warning.
Therefore, according to the present embodiment, the warning lamp 94 is turned on at the time when it is determined that the amount of sliding heat generated by the floating seal 76 is abnormally high, and at the same time, the deceleration command from the main hydraulic control device 104 is the main hydraulic pressure. It is output to the traveling motor 22 via the pump 98 and forced deceleration, that is, automatic regulation of the vehicle speed is performed. As a result, since the operator does not need to perform a deceleration operation while continuing the work and the traveling operation, a human error is avoided, and the problem associated with the sliding heat of the floating seal can be prevented more reliably.

Although the description of each embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, as a warning content, the engine speed may be set to a low speed or the engine may be stopped in addition to the vehicle speed reduction. Lubricating oil temperature rise is suppressed.

Alternatively, only forced deceleration may be performed without turning on the warning lamp 94. Further, the traveling rotator to which the output of the traveling motor 22 is transmitted may be a wheel in addition to the sprocket 24 as in the above embodiment.
Furthermore, in addition to the warning lamp 94 that is lit or blinking, a warning buzzer sound or a sound that is sounded, or both of these lamps and a buzzer may be included.

1 is a perspective view of a hydraulic excavator to which a warning control device of the present embodiment is applied. It is sectional drawing of the reduction gear incorporated in the traveling apparatus of the hydraulic shovel of FIG. It is explanatory drawing of the warning means in the hydraulic shovel of FIG. It is explanatory drawing of the warning means in other embodiment. It is a flowchart of the supply flow rate control of the traveling motor by the main hydraulic control apparatus of FIG.

Explanation of symbols

20 traveling device 22 traveling motor 24 sprocket (traveling rotating body)
26 Reduction gear 28 Housing 32 Casing 34 Tapered roller bearing (bearing)
42 Reduction gear chamber 44 Reduction gear mechanism 66 Oil temperature sensor (temperature detection means)
67 Warning Controller (Controller)
74 Sealing chamber 76 Floating seal 94 Warning lamp (Warning means)
104 Main hydraulic control device (warning means)

Claims (3)

In a construction machine including a traveling motor and a speed reducer that transmits the output of the traveling motor to a traveling rotating body,
A housing that surrounds the traveling motor; a casing that is rotatably supported on a peripheral surface of the housing via a bearing; and a reduction gear mechanism housed in an internal reduction gear chamber; and the casing between the casing and the housing Is disposed in the seal housing chamber adjacent to the reduction gear chamber via the bearing, and the seal housing chamber is liquid-tightly sealed from the outside. The speed reducer having an annular floating seal;
A temperature detecting means disposed in the seal housing chamber for detecting the temperature of the lubricating oil in the seal housing chamber;
A controller that determines the amount of heat generated by sliding by the floating seal from the detection result detected by the temperature detection means, and outputs a warning signal when the determination result is determined to be abnormal,
A warning control device for a construction machine, comprising warning means for generating a warning based on the warning signal.   The warning control device for a construction machine according to claim 1, wherein the warning means generates a warning for prompting a deceleration operation of the vehicle speed.   The warning control device for a construction machine according to claim 1 or 2, wherein the warning means outputs a signal for forcibly decelerating the vehicle speed to the traveling motor as the warning.

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