JP2023142592A - Construction equipment - Google Patents

Abstract

To provide construction equipment capable of measuring a tension amount of a crawler, even in a short work period and narrow work space, and preventing damage to a distance sensor due to sand and rock.SOLUTION: On a lower travel body 2, an upper turning body 4 is provided so as to freely turn. On a turning frame 17 as a bottom of the upper turning body 4, a distance sensor 18 for measuring a distance from a crawler 11 as a tension amount (loosening amount) of the crawler 11, is provided. Therefore, the distance sensor 18 is provided on the turning frame 17 at a higher position higher than the crawler 11 of the lower travel body 2. The distance sensor 18 can measure the distance to a top face side of the crawler 11 in a state in which the crawler 11 is on a ground surface.SELECTED DRAWING: Figure 1

Description

The present invention relates to a construction machine equipped with an undercarriage that travels by rotating crawler tracks.

A hydraulic excavator, which is a typical example of construction machinery, has a tracked lower body that can run on its own, an upper rotating body that is rotatably mounted on the lower body, and a rotating upper body that can rotate at the front of the upper rotating body. It is equipped with a working device installed in the

The undercarriage consists of a track frame with track side frames extending in the front-rear direction on both left and right sides, a drive wheel provided at the rear end which is one end of the track side frame in the length direction, and a track side frame with the length of the track side frame. It includes an idler wheel provided at the front end, which is the other end in the width direction, and a crawler belt wound around the drive wheel and the idler wheel. Further, the lower traveling body is provided with upper rollers that support the crawler track from below on the upper part of the track side frame.

In a tracked undercarriage, an idler wheel is provided so as to be movable in the front and rear directions with respect to the track side frame. Furthermore, a crawler belt tensioning device is provided between the idler wheels and the track side frame to adjust the tension of the crawler belt by the amount of grease injected into the adjuster cylinder. As a result, the undercarriage body measures the amount of tension (amount of slack) in the crawler track, and adjusts the amount of grease injected into the adjuster cylinder of the track tensioner based on the measurement result. The tension of the crawler belt can be adjusted so that an appropriate load is applied to the upper roller, the crawler belt, etc.

Here, when measuring the tension of the crawler belts, one of the crawler tracks is lifted by turning the upper rotating body 90 degrees with respect to the lower traveling body and pressing the working device against the ground. In this state, the distance from the track side frame to the crawler track is measured as the tension (looseness) of the track.

Therefore, a known hydraulic excavator has a configuration in which a distance sensor is provided at the lower part of the track side frame, and the distance from the track side frame to the track is measured by this distance sensor (Patent Document 1).

Japanese Unexamined Patent Publication No. 7-108961

Since the hydraulic excavator of Patent Document 1 is provided with a distance sensor at the lower part of the track side frame, in order to measure the tension of the crawler belt, the working device must be pressed against the ground and the crawler belt must be lifted. Therefore, in order to measure the tension of the crawler belt, a lot of working time is required to operate the working device, etc., and a large working space in which the working device can be turned in an extended state is required. Moreover, since the lower part of the truck side frame where the distance sensor is provided is a position where dirt and rocks are likely to come into contact with the vehicle during driving or work, there is a risk that the distance sensor may be damaged by the dirt and rocks.

The present invention has been made in view of the above-mentioned problems of the prior art.It is an object of the present invention to make it possible to measure the tension of a crawler track even in a short working time and in a narrow working space, and to make it possible to measure the tension of a crawler track even when the distance sensor is damaged by dirt and rocks. The purpose of the present invention is to provide construction machinery that can prevent such problems from occurring.

The present invention includes a self-propelled undercarriage, and an upper revolving body rotatably provided on the undercarriage, wherein the undercarriage has track side frames extending in the front-rear direction on both left and right sides. a truck frame provided at the same time, a driving wheel provided at one end in the length direction of the truck side frame, an idler wheel provided at the other end in the length direction of the truck side frame; A construction machine comprising: a crawler wound around an idler wheel; and an upper roller provided on the upper part of the track side frame to support the crawler from below; is provided with a distance sensor that measures the distance to the crawler track.

According to the present invention, the tension of the crawler track can be measured even in a short working time and in a narrow working space, and damage to the distance sensor due to dirt and rocks can be prevented.

FIG. 1 is a left side view showing a hydraulic excavator applied to a first embodiment of the present invention. FIG. 3 is a left side view showing the rear portion of the hydraulic excavator. FIG. 3 is a plan view showing a lower traveling body with crawler tracks omitted. FIG. 3 is a plan view showing a rotating frame and a distance sensor. FIG. 3 is a plan view showing the positional relationship between the lower traveling body and the distance sensor of the upper rotating body. FIG. 6 is a plan view similar to FIG. 5 illustrating a state in which the upper rotating body is rotated so that the distance sensor is placed at a position for measuring the tension of the track. It is a left side view showing a distance sensor (mobile sensor device) according to a second embodiment of the present invention together with a rear portion of a hydraulic excavator. It is a top view showing a turning frame and a distance sensor (mobile sensor device). FIG. 7 is a plan view showing a state in which the upper rotating body is rotated so that distance sensors are disposed above the drive wheels, above the upper rollers, and at measurement positions for the tension of the crawler belt. FIG. 7 is a left side view showing three distance sensors according to a modified example of the present invention together with the rear portion of the hydraulic excavator. FIG. 3 is a plan view showing the positional relationship between the lower traveling body and three distance sensors of the upper rotating body.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, as a representative example of a construction machine according to an embodiment of the present invention, a hydraulic excavator equipped with a tracked undercarriage will be taken as an example and explained in detail with reference to the accompanying drawings. In this embodiment, for the upper revolving body, the side where the working device is installed is the front side, and the side where the counterweight is installed is the rear side, and for the lower traveling body, the side where the idle wheels are installed is the front side, and the side where the driving wheels are installed. The side where is provided will be described as the rear side.

1 to 6 show a first embodiment of the invention. In FIG. 1, a tracked hydraulic excavator 1 includes a self-propelled lower traveling body 2, an upper rotating body 4 rotatably mounted on the lower traveling body 2 via a swing device 3, and an upper rotating body. A work device 5 is rotatably provided at the front part of the work device 4 and performs earth and sand excavation work. The turning device 3 is a mechanism for turning the upper rotating structure 4 on the lower traveling structure 2 . The swing device 3 has a swing ring 3A formed of an annular bearing provided between the track frame 6 of the lower traveling body 2 and the swing frame 17 of the upper swing structure 4, and a swing ring 3A that meshes with an inner ring of the swing ring 3A. A turning motor (not shown) for turning the rotating body 4 is provided. The state in which the front and rear of the upper rotating body 4 and the front and rear of the lower traveling body 2 are aligned as shown in FIG. 1 is referred to as a basic position.

The tracked undercarriage body 2 is for running on rough ground, muddy ground, etc. As shown in FIGS. 1 to 3, the lower traveling body 2 includes a track frame 6, a driving wheel 9, an idler wheel 10, a crawler belt 11, an upper roller 12, and a lower roller 13, which will be described later.

The track frame 6 includes a track center frame 7 located at the center in the left-right direction (width direction of the lower traveling body 2), and track side frames 8 provided on both left and right sides of the track center frame 7.

The track center frame 7 is formed as an X-shaped or H-shaped canned structure by welding a plurality of steel plates together. The track center frame 7 has a cylindrical portion 7A located at the center and protruding upward, and a turning wheel 3A of the turning device 3 is mounted on the cylindrical portion 7A. The centers of the cylindrical portion 7A and the turning ring 3A are the turning center O of the upper rotating body 4 (see FIGS. 3, 4, etc.).

The track side frames 8 are provided on both left and right sides of the track center frame 7 and extend in the front-rear direction. The track side frames 8 are arranged symmetrically on both left and right sides of the track center frame 7. The truck side frame 8 is formed as a rectangular cylinder extending in the front-rear direction. A drive wheel bracket 8A is provided at the rear end, which is one end in the length direction of the truck side frame 8. On the other hand, at the front end, which is the other end in the length direction of the track side frame 8, an idler wheel bracket 8B is provided. Furthermore, two upper rollers 12 are provided at the upper part of the track side frame 8 with an interval in the front-rear direction.

The drive wheel 9 is provided on a drive wheel bracket 8A located at the rear end of the track side frame 8, which is one end in the length direction. The drive wheel 9 includes a reduction gear 9A attached to the drive wheel bracket 8A, a travel motor (not shown) connected to the input side of the reduction gear 9A, and a sprocket 9B provided on the output side of the reduction gear 9A. , is equipped with. The outer peripheral side of the sprocket 9B meshes with the crawler belt 11.

The idler wheel 10 is provided on an idler wheel bracket 8B located at the front end, which is the other longitudinal end of the track side frame 8. The idler wheel 10 is attached to the idler wheel bracket 8B so as to be movable in the front-rear direction. Further, a crawler belt tensioning device (none of which is shown) consisting of a coil spring, an adjuster cylinder, etc. is provided between the idler wheel 10 and the track side frame 8. This crawler belt tensioning device can adjust the tension of the crawler belt by adjusting the amount of grease injected into the adjuster cylinder.

The crawler belt 11 is wound around the driving wheel 9 and the idler wheel 10. For example, the crawler track 11 includes a large number of track links connected in the circumferential direction and a large number of track shoes attached to each track link. Here, even if the crawler belt 11 is slightly abraded, for example, at the connecting portion between the track links, the abrasion of the many track links is added up, causing the crawler belt 11 to stretch and become slack. Furthermore, the crawler belt 11 becomes loose due to wear that occurs between the crawler belt 11 and the sprocket 9B of the drive wheel 9, the idler wheel 10, the upper roller 12, and the lower roller 13. If the crawler belt 11 becomes loose in this way, there is a risk that it will not be possible to smoothly switch between forward and backward, the running noise will become louder, and vibrations will occur. It is desirable to adjust to

The upper roller 12 is provided on the top of the track side frame 8. The upper roller 12 supports the crawler belt 11 from below. For example, two upper rollers 12 are provided at intervals in the front-rear direction.

As shown in FIGS. 1 and 2, the lower roller 13 is provided at the lower part of the track side frame 8. As shown in FIGS. The lower roller 13 presses the crawler belt 11 against the ground from above. For example, a plurality of lower rollers 13, for example seven lower rollers, are provided at intervals in the front-rear direction.

Next, the configuration of the upper revolving body 4 will be explained. As shown in FIG. 1, the upper revolving body 4 includes a revolving frame 17, which will be described later, a cab 14 mounted on the left front side of the revolving frame 17 and forming a driver's cab inside, and a rear part of the revolving frame 17. A building housing a counterweight 15 that balances the weight of the work device 5, an engine, a hydraulic pump (none of which are shown), etc. located between the cab 14 and the counterweight 15 and mounted on the revolving frame 17. It is equipped with 16. Inside the cab 14, there is a driver's seat where the operator sits, and operation levers (none of which are shown) for driving and working that operate the hydraulic excavator 1 and are located in front of, on the left side, and on the right side of the driver's seat. It is provided.

The revolving frame 17 forms the bottom of the upper revolving body 4. As shown in FIG. 4, the swing frame 17 includes a flat bottom plate 17A made of a thick steel plate or the like that extends in the front-rear direction, and is erected on the bottom plate 17A and extends in the front-rear direction at a predetermined interval in the left-right direction. A left vertical plate 17B, a right vertical plate 17C, a plurality of left overhang beams 17D extending to the left from the bottom plate 17A and the left vertical plate 17B at intervals in the front and back direction, and a plurality of left overhang beams 17D extending from the bottom plate 17A and the right vertical plate 17C at intervals in the front and rear direction. A plurality of right overhang beams 17E extending to the right side, a left side frame 17F attached to the tip of the left overhang beam 17D extending in the front-rear direction, and a left side frame 17F attached to the front end of the right overhang beam 17E extending in the front-rear direction. The right side frame 17G is attached in the state shown in FIG.

The rotating frame 17 also includes a plurality of undercovers 17H to cover between the bottom plate 17A, the left vertical plate 17B, and the right vertical plate 17C (at the back of the bottom plate 17A, the left vertical plate 17B and the right (Only shown between vertical plate 17C). Furthermore, the bottom plate 17A has a joint insertion hole 17J into which a center joint (not shown) is inserted. The center of the joint insertion hole 17J is the pivot center O of the upper rotating body 4.

For example, the left side frame 17F and the right side frame 17G are formed of pipe members. The left side frame 17F is located above the left crawler belt 11 with the working device 5 disposed on the front side of the lower traveling body 2. Similarly, the right side frame 17G is located above the right crawler belt 11 with the working device 5 disposed in front of the lower traveling body 2.

The distance sensor 18 is provided on the revolving frame 17 that forms the bottom of the upper revolving structure 4 . The distance sensor 18 measures the distance S1 from the distance sensor 18 to the crawler belt 11. As shown in FIG. 4, the distance sensor 18 is provided near the rear of the left side frame 17F of the swing frame 17. As the distance sensor 18, for example, a non-contact type sensor using infrared rays, laser, ultrasonic waves, etc. is used. For sites where dust and dirt are scattered, distance sensors that use ultrasonic waves, which are not easily affected by dust and dirt, are suitable. Further, the distance sensor 18 has, for example, a cylindrical appearance, and is screwed while being vertically inserted into an insertion hole formed in the lower part of the left side frame 17F.

The mounting position of the distance sensor 18 with respect to the upper revolving structure 4 will be explained. The distance sensor 18 is located near the middle between the driving wheel 9 and the upper roller 12 on the rear side, and near the middle between the idler wheel 10 and the upper roller 12 on the front side when the upper rotating structure 4 performs a turning operation on the lower traveling body 2. It is arranged at a position passing near the middle of at least one of the two.

Here, as shown in FIG. 2, a straight line extending vertically through the center of the sprocket 9B of the drive wheel 9 provided on the left track side frame 8C is a line A (center point A in the plan view of FIG. ), and a straight line extending vertically through the center of the upper roller 12 on the left rear side is defined as line B (illustrated as center point B in plan view in FIG. 3), then the drive wheel 9 and the rear side The position where the left crawler track 11 loosens significantly between it and the upper roller 12 is near the middle between the drive wheel 9 and the rear upper roller 12, specifically, between the drive wheel 9 and the rear upper roller 12. midpoint C (in the left side view of FIG. 2, it is shown as a line C extending vertically through midpoint C). Specifically, if the distance between line A and line B is dimension L, then the distance between line A and midpoint C (line C) is dimension L/2. Similarly, the distance between line B and intermediate point C (line C) is the dimension L/2.

As shown in FIG. 3, the intermediate point C (line C) is located on a circular arc Q1 drawn from the turning center O with a radius R1. Further, as shown in FIG. 4, a distance sensor 18 is arranged at a position passing through the arc Q1 of the left side frame 17F. As a result, as shown in FIG. 5, the distance sensor 18 and the intermediate point C (line C) where the crawler belt 11 becomes largely slack between the drive wheel 9 and the upper roller 12 on the rear side are arranged on the circular arc Q1. There is.

That is, as shown by P1 (two-dot chain line) in FIG. 6, the upper rotating body 4 is rotated approximately 5 degrees counterclockwise in plan view from the basic position P0 in FIG. 5, and the distance sensor 18 is set at the intermediate point. It can be placed directly above C. In this state, the distance sensor 18 measures the distance S1 between the distance sensor 18 and the left crawler track 11. Thereby, the amount of tension (amount of slack) of the crawler belt 11 on the left side can be measured based on the distance S1 at a position where the left crawler belt 11 is significantly slackened near the middle between the drive wheel 9 and the upper roller 12 on the rear side.

Further, as shown in FIG. 3, a straight line extending vertically through the center of the idler wheel 10 provided on the left side truck side frame 8C is defined as a line D (shown as center point D), and the upper left roller When a straight line extending vertically through the center of the roller 12 is defined as a line E (shown as the center point E), the position where the left crawler track 11 becomes largely slack near the middle between the idler wheel 10 and the front upper roller 12 is as follows. This is the intermediate point F between the idler wheel 10 and the front upper roller 12. The intermediate point F between the idler wheel 10 and the front upper roller 12 is located on or close to the arc Q1. As a result, the intermediate point F, where the left crawler belt 11 slackens significantly near the middle between the idler wheel 10 and the front upper roller 12, is located on the same arc Q1 as the distance sensor 18.

That is, as shown by P2 (two-dot chain line) in FIG. 6, in a position where the upper rotating body 4 is rotated approximately 80 degrees clockwise in plan view, the distance sensor 18 should be placed directly above the intermediate point F. I can do it. In this state, the distance sensor 18 measures the distance between the distance sensor 18 and the left crawler track 11. Thereby, the amount of tension (amount of slack) of the left crawler belt 11 can be measured at a position near the middle between the idler wheel 10 and the upper roller 12 on the front side, where the left crawler belt 11 is greatly slackened.

On the other hand, a straight line extending vertically through the center of the drive wheel 9 provided on the right side truck side frame 8D is defined as a line G (shown as center point G), and passing through the center of the upper roller 12 on the right rear side. A straight line extending in the vertical direction is defined as a line H (illustrated as a center point H). In this case, the position where the right crawler belt 11 slackens significantly near the middle between the drive wheel 9 and the rear upper roller 12 is the midpoint J between the drive wheel 9 and the rear upper roller 12. An intermediate point J between the drive wheel 9 and the upper roller 12 on the rear side is located on or close to the arc Q1. As a result, the intermediate point J where the right crawler belt 11 slackens significantly near the middle between the drive wheel 9 and the rear upper roller 12 is located on the same arc Q1 as the distance sensor 18.

That is, by rotating the upper revolving body 4, the distance sensor 18 can be placed directly above the intermediate point J. In this state, the distance sensor 18 measures the distance between the distance sensor 18 and the right crawler track 11. Thereby, the amount of tension (amount of slack) of the crawler belt 11 on the right side can be measured at a position where the crawler belt 11 on the right side is largely slackened near the middle between the drive wheel 9 and the upper roller 12 on the rear side.

Furthermore, a straight line extending vertically through the center of the idler wheel 10 provided on the right side truck side frame 8D is defined as a line K (shown as center point K), and a straight line extending vertically through the center of the upper roller 12 on the right front side is defined as a line K (shown as center point K). A straight line extending in the direction is defined as a line M (illustrated as a center point M). In this case, the position where the right crawler belt 11 slackens significantly near the middle between the idler wheel 10 and the front upper roller 12 is the intermediate point N between the idler wheel 10 and the front upper roller 12. The intermediate point N between the idler wheel 10 and the front upper roller 12 is located on or close to the arc Q1. As a result, the intermediate point N, where the right crawler belt 11 slackens significantly near the middle between the idler wheel 10 and the front upper roller 12, is located on the same arc Q1 as the distance sensor 18.

That is, by rotating the upper revolving body 4, the distance sensor 18 can be placed directly above the intermediate point N. In this state, the distance sensor 18 measures the distance between the distance sensor 18 and the right crawler track 11. Thereby, the amount of tension (the amount of slack) of the crawler belt 11 on the right side can be measured at a position where the right crawler belt 11 is largely slackened near the middle between the idler wheel 10 and the front upper roller 12.

In this way, in the first embodiment, the distance is measured by the distance sensor 18 at two points, intermediate point C and intermediate point F, with respect to the crawler track 11 wound around the left track side frame 8C, and The distance to the crawler belt 11 wound around the frame 8D is measured at two points, intermediate point J and intermediate point N, and the amount of slack in the crawler belt 11 is measured at a total of four points. In addition, it is also possible to measure the distance to one intermediate point with respect to the crawler track 11 of the left track side frame 8C, and to measure the distance of one intermediate point with respect to the crawler track 11 of the right track side frame 8D. good.

Next, an example of a work procedure for measuring the amount of tension (the amount of slack) of the left and right crawler tracks 11 using the distance sensor 18 provided on the left side frame 17F of the revolving frame 17 of the upper revolving structure 4 will be described.

When measuring the amount of tension (the amount of slack) in the crawler belt 11, a correct measurement value can be obtained by keeping the measurement environment constant. First, the hydraulic excavator 1 is placed on a flat place suitable for measuring the tension of the crawler belt 11. The space required in this case is a space in which the working device 5 can be stood up and the revolving upper body 4 can be rotated with the working device 5 completely folded. In other words, the tension of the crawler belt 11 can be measured by ensuring a space in which the upper rotating structure 4 can turn. Further, as a preparatory operation before measuring the tension of the crawler belt 11, in order to keep the state of the crawler belt 11 constant, the hydraulic excavator 1 (lower traveling body 2) is slowly advanced and stopped.

When the hydraulic excavator 1 is stopped, the working device 5 is started up and the entire working device 5 is folded. Next, with the tension measurement switch of the crawler belt 11 turned on, the upper rotating body 4 is rotated once. At this time, a controller (not shown) mounted on the hydraulic excavator 1 calculates the distance sensor 18 when the distance sensor 18 is disposed on the intermediate point C based on the turning angle of the upper rotating structure 4 with respect to the lower traveling structure 2. The distance S1 from to the crawler track 11 is taken out. Similarly, the distance from the distance sensor 18 to the crawler belt 11 when placed on the intermediate points F, J, and N is obtained.

Thereby, the tension of the crawler belt 11 including the distance S1 from the distance sensor 18 to the left crawler belt 11 can be compared with the dimension set as the threshold value. If the measured tension of the crawler belt 11 exceeds a threshold value, the tension of the crawler belt 11 is adjusted.

The hydraulic excavator 1 according to this embodiment has the above-described configuration, and its operation will be described next.

The operator can make the lower traveling body 2 travel by boarding the cab 14, sitting in the driver's seat, starting the engine, and operating the travel control lever and the like. On the other hand, the operator can perform a turning operation of the upper revolving structure 4, excavating earth and sand with the working device 5, etc. by operating a working operating lever.

The crawler belt 11 of the hydraulic excavator 1 will loosen (relatively elongation). Therefore, in the hydraulic excavator 1, the tension of the crawler belt 11 is periodically measured and the tension of the crawler belt 11 is adjusted. Adjustment of the tension of the crawler track 11 is performed by injecting grease into the adjuster cylinder of the track tensioning device provided between the idler wheel 10 and the track side frame 8 to increase the tension of the track 11. The slack can be reduced.

Thus, according to the present embodiment, the revolving frame 17 serving as the bottom of the upper rotating body 4 that is rotatably provided on the lower traveling body 2 is provided with a distance from the crawler belt 11 to the tension amount (slack amount) of the crawler belt 11. ) is provided. Therefore, the distance sensor 18 is provided on the revolving frame 17 at a higher position than the crawler belt 11 of the lower traveling body 2. On top of this, the distance sensor 18 measures the distance to the upper surface side of the crawler belt 11.

Thereby, in this embodiment, the amount of tension (the amount of slack) of the crawler belt 11 can be measured without lifting the crawler belt 11. As a result, the tension of the crawler belt 11 can be easily measured even in a short working time and in a narrow working space.

Furthermore, since the distance sensor 18 is installed on the revolving frame 17 at a higher position than the lower traveling body 2, even if dirt or rocks are thrown up during driving or work, the sand or rocks will collide with the distance sensor 18. It's getting harder to do. Thereby, the distance sensor 18 can be prevented from being damaged by dirt and rocks, and durability and reliability can be improved.

The distance sensor 18 is located near the middle between the driving wheel 9 and the upper roller 12 on the rear side, and near the middle between the idler wheel 10 and the upper roller 12 on the front side when the upper rotating structure 4 performs a turning operation on the lower traveling body 2. It is located in a position that passes through both. Therefore, by simply turning the upper rotating body 4 once on the lower traveling body 2, the tension of the left crawler track 11 can be measured at the intermediate point C and the intermediate point J between the drive wheel 9 and the upper roller 12 on the rear side. , the tension of the right crawler belt 11 can be measured at intermediate points F and N between the idler wheel 10 and the front upper roller 12. As a result, the tension can be measured at two locations for one crawler track 11, thereby improving the reliability of the measured values.

Also, intermediate points C and J near the middle between the driving wheel 9 and the upper roller 12 on the rear side, intermediate points F and N near the middle between the idler wheel 10 and the upper roller 12 on the front side are the crawler track 11 Since this is the part where the slack of the crawler belt 11 is greatest, the amount of slack of the crawler belt 11 can be clearly measured.

Next, FIGS. 7 to 9 show a second embodiment of the present invention. The feature of this embodiment is that the distance sensors are located at three locations: above the drive wheel, above the upper roller, and above near the middle between the drive wheel and the upper roller; above the idler wheel; above the upper roller; and above the idler wheel. It is located at a position where the distance to the crawler track can be measured at both of the three locations above near the middle of the upper roller. Further, the distance sensor is movably attached to the revolving upper structure. Specifically, the distance sensor is provided so as to be movable over a distance corresponding to the range from the drive wheel to the upper roller or the range from the idler wheel to the upper roller. In addition, in the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof will be omitted.

In FIG. 7, a mobile distance sensor 21 as a distance sensor is provided on the revolving frame 17 of the upper revolving structure 4. As shown in FIG. As shown in FIG. 8, the mobile distance sensor 21 is located on the rear side of the rotating frame 17 and is attached to the undercover 17H between the left vertical plate 17B and the right vertical plate 17C. The mobile distance sensor 21 is attached to the upper revolving body 4 so as to be movable in the front and rear directions. Specifically, the mobile distance sensor 21 includes a sensor main body 21B that is movable over a distance corresponding to the range from the drive wheel 9 to the upper roller 12 on the rear side or the range from the idler wheel 10 to the upper roller 12 on the front side. We are prepared.

For example, the mobile distance sensor 21 includes a long box-shaped casing 21A extending in the front-rear direction and attached to the undercover 17H, a sensor main body 21B provided movably in the front-rear direction along the casing 21A, and a sensor main body 21A. A moving mechanism 21C for moving 21B to a predetermined position is provided. The sensor main body 21B uses a non-contact type sensor that uses infrared rays, lasers, ultrasonic waves, etc., like the distance sensor 18 of the first embodiment. Furthermore, the moving mechanism 21C has a configuration in which the sensor main body 21B is attached to a toothed belt extending over the entire length of the casing 21A, and the toothed belt is rotated by a motor whose rotation speed can be controlled. Note that the moving mechanism 21C may be configured to move the sensor body 21B using a ball screw or a rack and pinion.

As shown in FIG. 9, the movement range of the sensor body 21B by the mobile distance sensor 21 is above the drive wheel 9, above the rear upper roller 12, and near the middle between the drive wheel 9 and the rear upper roller 12. The distance to the crawler belt 11 is determined at both the upper three locations, the upper part of the idler wheel 10, the upper part of the front upper roller 12, and the upper part near the middle between the idler wheel 10 and the front upper roller 12. This is within the measurable range.

Specifically, the movement range of the sensor body 21B is in front of an arc Q2 with a radius R2 that passes through the center points B, E, H, and M of the upper roller 12 with the center of rotation O as the center, and is centered on the center of rotation O. It is set on the rear side of an arc Q3 having a radius R3 passing through the center points A, G of the sprocket 9B of the driving wheel 9 and the center points D, K of the idler wheel 10.

As shown by P3 (two-dot chain line) in FIG. The distance sensor 21 moves the sensor body 21B to the position of the circular arc Q3. Thereby, the sensor main body 21B is located on the center point A of the sprocket 9B of the driving wheel 9 at P3 of the upper revolving structure 4, and the distance S2 between the sensor main body 21B and the left crawler track 11 can be measured. .

Next, as shown by P4 (two-dot chain line) in FIG. , the mobile distance sensor 21 moves the sensor body 21B to the position of the circular arc Q1. As a result, the sensor main body 21B is located on the intermediate point C between the drive wheel 9 and the upper roller 12 on the rear side at P4 of the upper revolving structure 4, and the distance between the sensor main body 21B and the left crawler track 11 is S3 can be measured.

Furthermore, as shown by P5 (two-dot chain line) in FIG. The mobile distance sensor 21 moves the sensor body 21B to the position of the circular arc Q2. Thereby, the sensor main body 21B is located on the center point B of the upper roller 12 on the rear side at P5 of the upper revolving structure 4, and the distance S4 between the sensor main body 21B and the left crawler track 11 can be measured. .

In this case, wear of the crawler belt 11, drive wheel 9 (sprocket 9B), and upper roller 12 can be recognized from changes in distances S2 and S4. As a result, it is possible to calculate the accurate amount of slack in the crawler belt 11 based on the distance S3, taking into account the wear of the crawler belt 11, the drive wheel 9 (sprocket 9B), and the upper roller 12 (subtracting the wear amount). can.

Note that the measurement procedures at center point D, center point E, intermediate point F, center point G, center point H, intermediate point J, center point K, center point M, and intermediate point N also apply to center point A, center point B, Since this is the same as the measurement procedure at intermediate point C, the explanation will be omitted.

Thus, in the second embodiment configured in this manner, substantially the same functions and effects as those of the first embodiment described above can be obtained. In particular, in the second embodiment, the sensor main body 21B of the mobile distance sensor 21 is located above the drive wheel 9, above the rear upper roller 12, and near the middle between the drive wheel 9 and the rear upper roller 12. The distance to the crawler track 11 is measured both at three points above, above the idler wheel 10, above the upper roller 12 on the front side, and at three points above near the middle between the idler wheel 10 and the upper roller 12 on the front side. placed in a possible location. Thereby, the mobile distance sensor 21 can calculate the accurate amount of slack in the crawler belt 11 based on the distance S3 after subtracting the wear of the crawler belt 11, drive wheel 9 (sprocket 9B), and upper roller 12. Can be done.

Further, the sensor main body 21B of the mobile distance sensor 21 is movably attached to the upper rotating body 4. Specifically, the sensor body 21B of the mobile distance sensor 21 is movable over a distance corresponding to the range from the drive wheel 9 to the upper roller 12 on the rear side or the range from the idler wheel 10 to the upper roller 12 on the front side. It includes a sensor main body 21B. Thereby, measurement can be performed by moving one sensor body 21B even at measurement positions at different distances from the turning center O.

In the first embodiment, the rotating frame 17 of the upper rotating structure 4 is provided with an intermediate point C between the drive wheel 9 and the upper roller 12 on the rear side (on an arc Q1 drawn with a radius R1 from the center of rotation O). ), and one distance sensor 18 is provided. However, the present invention is not limited to this, and may be configured, for example, as modified examples shown in FIGS. 10 and 11. Specifically, as shown in FIG. 11, in addition to the distance sensor 18 provided on the arc Q1, one distance sensor 31 is provided on the arc Q2 of the second embodiment, and one distance sensor 31 is provided on the arc Q3. A configuration in which a distance sensor 32 is provided may also be used. As a result, as in the second embodiment, the accurate amount of slack in the crawler belt 11 can be calculated after subtracting the wear of the crawler belt 11, drive wheel 9 (sprocket 9B), idler wheel 10, and upper roller 12. Can be done.

In the first embodiment, with respect to the left crawler track 11, there is a position where the left crawler track 11 is greatly slackened near the middle between the drive wheel 9 and the rear upper roller 12 (midpoint C), and a position where the left crawler track 11 is greatly slackened near the middle between the drive wheel 9 and the rear upper roller 12, and The tension (looseness) is measured at two locations: the position where the left crawler 11 slackens significantly near the middle with the upper roller 12 (intermediate point F), and the tension (looseness) is measured at the intermediate points J and N for the right crawler 11 as well. The case where the amount of tension (amount of slack) is measured at two locations is illustrated. However, the present invention is not limited to this, and may be configured to measure the tension (looseness) at one location for the left crawler belt 11 and at one location for the right crawler belt 11.

In the first embodiment, the distance sensor 18 is provided on the left side frame 17F of the swing frame 17, and in the second embodiment, the mobile distance sensor 21 as a distance sensor is provided on the undercover 17H of the swing frame 17. was explained using an example. However, the present invention is not limited to this, and the distance sensor 18 and the mobile distance sensor 21 may be provided at other locations on the rotating frame 17.

Furthermore, in the embodiment, the hydraulic excavator 1 has been described as an example of the construction machine. However, the present invention is not limited to this, and can be widely applied to other construction machines equipped with a swing device, such as a hydraulic crane.

1 Hydraulic excavator (construction machinery)
2 Lower traveling body 3 Swivel device 4 Upper rotating body 6 Track frame 8 (8C, 8D) Track side frame 9 Drive wheel 9B Sprocket 10 Idler wheel 11 Crawler 12 Upper roller 18, 31, 32 Distance sensor O Turning center 21 Movable distance Sensor (distance sensor)
21B Sensor body A, B, D, E, G, H, K, M line (center point)
C, F, J, N midpoint (line)
S1, S2, S3, S4 Distance from distance sensor to crawler track

Claims (5)

comprising a self-propelled lower traveling body and an upper rotating body rotatably provided on the lower traveling body,
The lower running body is
A truck frame with truck side frames extending in the front and back direction on both the left and right sides,
a drive wheel provided at one longitudinal end of the track side frame;
an idler wheel provided at the other longitudinal end of the track side frame;
a crawler belt wound around the driving wheel and the idler wheel;
an upper roller provided on the upper part of the track side frame and supporting the crawler track from below;
In construction machinery equipped with
A construction machine characterized in that a distance sensor for measuring a distance to the crawler belt is provided at the bottom of the upper revolving body. The construction machine according to claim 1,
The distance sensor is disposed at a position where the distance sensor passes through at least one of near the middle between the driving wheel and the upper roller, or near the middle between the idler wheel and the upper roller when the upper revolving body performs a turning operation. A construction machine characterized by: The construction machine according to claim 1,
The distance sensor is arranged at three locations: above the drive wheel, above the upper roller, and above near the middle between the drive wheel and the upper roller, or above the idler wheel, above the upper roller, and above the idler wheel. A construction machine characterized in that the construction machine is arranged at a position where the distance to the crawler track can be measured at one or both of three locations above the middle of the track and the upper roller. The construction machine according to claim 1,
The construction machine is characterized in that the distance sensor is attached to the upper revolving body so as to be movable in the front and rear directions. The construction machine according to claim 4,
The construction machine is characterized in that the distance sensor is provided so as to be movable over a distance corresponding to a range from the driving wheel to the upper roller or a range from the idler wheel to the upper roller.

Images