Description
AN APPARATUS FOR CONTROLLING THE TENSION OF A TRACK IN HEAVY EQUIPMENTS
Technical Field
[1] The present invention relates to an apparatus for controlling the tension of an endless track in heavy equipment, and more particularly, to an apparatus for controlling the tension of a track in heavy equipment and effectively absorbing vibrations and shocks occurring at the track. Background Art
[2] In a wheeled heavy-duty vehicle (heavy equipment) for constructions and agriculture, wheels are connected to a main body of the vehicle using suspension so that vibrations and shocks can be absorbed by the suspension when the vehicle starts, moves, stops, and operates.
[3] However, in a tracked heavy-duty vehicle in which track frames are attached to a lower structure of a vehicle body for supporting tracks, an additional suspension structure is not provided, such that vibrations and shocks transmitted from the tracks cannot be effectively absorbed and dampened. Therefore, components of the lower structure of the vehicle body can be damaged by vibrations and shocks directly transmitted from the tracks to the vehicle body, causing fatigue failures and decreasing lifespan of the components. Furthermore, an operator of the tracked vehicle may suffer from the vibrations and shocks.
[4] Meanwhile, the tracks of the heavy-duty vehicle become loose with use because of friction between the tracks and the ground, such that the tension of the tracks must be periodically adjusted. FIG. 8 illustrates an example of a conventional track tension controlling apparatus for a heavy-duty vehicle. In the conventional track tension controlling apparatus, an idler 103 supporting a track 101 is connected to an idle guide 105, and a tension adjustment rod 107 is connected to a rear end of the idler guide 105. A threaded portion 109 of the rear end of the idler guide 105 is coupled to a fixed nut 113 of a track frame 111.
[5] In the conventional tension controlling apparatus, the position of the threaded portion
109 relative to the fixed nut 113 can be varied by rotating the tension adjustment rod 107 to adjust the position of the idler 103 relative to the track 101 and the tension of the track 101.
[6] Although the tension of the track 101 can be adjusted using only the tension adjustment rod 107 and the fixed nut 113, it takes much time to rotate the tension adjustment rod 107 for adjusting the tension of the track 101. Moreover, vibrations and
shocks transmitted from the track 101 to the idler 103 cannot be absorbed.
[7] Therefore, tension controlling apparatuses with a shock-absorbing unit have been introduced.
[8] An example of a tension controlling apparatus with a shock-absorbing unit is illustrated in FIG. 9. Referring to FIG. 9, an idler 103 disposed in a front portion of a track 101 is supported by an idler guide 105, and a vibration spring 115 is coupled to a rear portion of the idler guide 105 for absorbing vibrations and shocks. A cylinder 117 is coupled to a rear portion of the vibration spring 115 for adjusting the tension of the track 101. A distance between the vibration spring 115 and a track frame 111 to which the cylinder 117 is fixed can be varied by filling lubricant grease in the cylinder 117 through an inlet port 119 of the cylinder 117 or discharging the grease from the cylinder 117 through the inlet port 119. Therefore, the idler 103 can be moved by varying the distance between the vibration spring 115 and the track frame 111 in order to adjust the tension of the track 101.
[9] However, since the vibration spring 115 is usually formed of steel, vibrations and shocks transmitted from the track 101 to the tension adjustment unit 11 through the idler 103 cannot be effectively absorbed and dampened. Furthermore, it is inconvenient to fill grease into the cylinder 117, and an additional device is necessary to fill grease into the cylinder 117. Moreover, the tension of the track 101 cannot be immediately adjusted by expanding or retracting the cylinder 117 using grease.
[10] In addition, since the cylinder 117 in which lubricant grease is filled is not durable, the cylinder 117 should be replaced with a new one periodically, for example, every two or three years. Disclosure of Invention
Technical Problem
[11] Accordingly, the present invention is directed to a track tension controlling apparatus that substantially obviates one or more of the problems due to limitations and disadvantages of the related art. The track tension controlling apparatus is provided for easily, simply, and rapidly adjusting the tension of a track in heavy equipment and effectively absorbing vibrations and shocks occurring at the track. Technical Solution
[12] According to an aspect of the present invention, there is provided an apparatus for controlling tension of a track in heavy equipment, the apparatus including: an idler directly supporting a heavy-equipment endless track; an idler guide to which the idler is rotatably connected; an anti- vibration spring connected to a rear portion of the idler guide for absorbing vibrations transmitted from the idler; and a tension adjustment unit connected to a rear portion of the anti-vibration spring for adjusting a distance between
the idler and a track frame.
[13] The tension adjustment unit includes two male screw rods and a nut-shaped rotation member for easily and rapidly adjusting the distance between the idler and the track frame.
[14] The anti-vibration spring includes a plurality of anti-vibration rubber plates and a plurality of anti- vibration steel plates that are alternately arranged so that vibrations and shocks transmitted from the track can be effectively absorbed and dampened when a heavy-duty vehicle starts, travels, operates, and stops. Therefore, an operator of the heavy-duty vehicle can conveniently and efficiently works, and components of the heavy-duty vehicle can have a much longer lifespan.
Advantageous Effects
[15] According to the present invention, the anti-vibration spring of the track tension controlling apparatus is formed by alternately arranging rubber plates and steel plates for absorbing and dampening vibrations and shocks transmitted from a track to a heavy-duty vehicle body. Therefore, the heavy-duty vehicle body can be protected from the vibrations and shocks transmitted from the track when the heavy-duty vehicle operates, and thus components constituting a lower structure of the heavy duty vehicle can have a long lifespan. Particularly, in the case where the track of the heavy-duty vehicle that is directly connected to the track tension controlling apparatus is a rubber crawler, components of the heavy-duty vehicle can have a much longer lifespan by using the track tension controlling apparatus, and an operator can conveniently drive and operate the heavy-duty vehicle, thereby increasing operation efficiency.
[16] Furthermore, the track tension controlling apparatus of the present invention includes the male screw rods and the nut-shaped rotation member coupled with the male screw rods. Thus, the distance between the male screw rods and can be easily varied by rotating the rotation member, and thus the tension of the track can be easily adjusted by varying the distance between the male screw rods. Therefore, according to the present invention, the tension of the track can be easily adjusted, and it is not necessary to periodically replace the track tension controlling apparatus since the male screw rods and the rotation member are very durable. Brief Description of the Drawings
[17] FIG. 1 is a side illustrating a heavy equipment track including a tack tension controlling apparatus according to an embodiment of the present invention.
[18] FIG. 2 is a perspective view illustrating the track tension controlling apparatus of
FIG. 1, according to an embodiment of the present invention.
[19] FIG. 3 is a plan view illustrating the track tension controlling apparatus of FIG. 2, according to an embodiment of the present invention.
[20] FIG. 4 is a enlarged side view illustrating the track tension controlling apparatus of
FIG. 2, according to an embodiment of the present invention.
[21] FIG. 5 is a front view illustrating an anti- vibration spring of the track tension controlling apparatus according to an embodiment of the present invention.
[22] FIG. 6 is a front view illustrating a tension adjustment unit of the track tension controlling apparatus according to an embodiment of the present invention.
[23] FIG. 7 is a graph illustrating the amplitude of vibration at a top portion of a heavy- duty vehicle in the cases where the heavy-duty vehicle using the track tension controlling apparatus of the present invention and a conventional track tension controlling apparatus.
[24] FIG. 8 is a front view illustrating an example of a conventional track tension controlling apparatus for heavy equipment.
[25] FIG. 9 is a front view illustrating another example of a conventional track tension controlling apparatus for heavy equipment. Best Mode for Carrying Out the Invention
[26] The present invention will now be described with respect to the accompanying drawings, in which exemplary embodiments of the present invention are shown.
[27] FIG. 1 is a side view illustrating a heavy equipment track including a tack tension controlling apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view illustrating the track tension controlling apparatus for heavy equipment of FIG. 1, according to an embodiment of the present invention. Referring to FIGs. 1 and 2, the track tension controlling apparatus is disposed between an endless track 1 and a track frame 3 for adjusting the tension of the track 1 and absorbing vibrations and shocks generating at the track 1. The endless track 1 is used as a transportation unit for a heavy-duty vehicle, and the track frame 3 forms a lower structure of the heavy-duty vehicle. The track tension controlling apparatus includes an idler 5 directly supporting the endless track 1, an idler guide 7 to which the idler 5 is rotatably connected, an anti- vibration spring 9 connected to a rear portion of the idler guide 7 for absorbing vibrations transmitted from the idler 5, and a tension adjustment unit 11 connected to a rear portion of the anti-vibration spring 9 for adjusting a distance between the idler 5 and the track frame 3,
[28] As shown in FIG. 5, the anti-vibration spring 9 includes a plurality of anti- vibration rubber plates 9a and a plurality of anti-vibration steel plates 9b that are alternately arranged. The anti- vibration spring 9 can be formed by disposing the anti- vibration steel plates 9b at regular intervals in a die and injecting rubber into the die at a predetermined pressure to form the anti-vibration rubber plates 9a between the anti- vibration steel plates 9b. Therefore, the anti- vibration spring 9 can be formed as one
part.
[29] One end of the anti-vibration spring 9 is fixed to a connection plate 7a of the idler guide 7, and the other end of the anti- vibration spring 9 is fixed to a front connection plate 1 Ia of the tension adjustment unit 11. Therefore, the anti-vibration spring 9 can absorb vibrations and shocks between the idler guide 7 and the tension adjustment unit 11.
[30] As shown in FIG. 6, the tension adjustment unit 11 has a bolt-nut structure. In detail, the tension adjustment unit 11 includes two male screw rods 1 Ib and 1 Ic and a nut- shaped (female screw shaped) rotation member Hd.
[31] The tension adjustment unit 11 further includes the front connection plate 11a fixedly connected to the anti- vibration spring 9 and a rear connection plate l ie connected to the track frame 3.
[32] The front connection plate 1 Ia is formed integrally with the male screw rod 1 Ib, and the rear connection plate 1 Ie is formed integrally with the male screw rod l ie.
[33] Therefore, when the front connection plate 1 Ia is connected to the anti- vibration spring 9 and the rear connection plate 1 Ie is connected to the track frame 3, the male screw rods 1 Ib and 1 Ic cannot be rotated. In this state, the distance between the male screw rods 1 Ib and 1 Ic can be varied by rotating the rotation member 1 Id. Therefore, the idler 5 connected to the tension adjustment unit 11 through the idler guide 7 and the anti- vibration spring 9 can be moved by varying the distance between the male screw rods 1 Ib and 1 Ic, and thus the tension of the track 1 can be adjusted by the movement of the idler 5.
[34] As explained in FIGs. 1 to 4, the track tension controlling apparatus is installed between the track 1 used as a transportation unit of a heavy-duty vehicle and the track frame 3 forming a lower structure of the heavy-duty vehicle. The idler 5 is not directly connected to a driving unit. That is, the idler 5 can freely turn and support the track 1.
[35] In this state, vibrations and shocks generating when the heavy-duty vehicle starts, moves, operates, or stops are transmitted from the track 1 to the anti- vibration spring 9 through the idler 5 and the idler guide 7. At the anti- vibration spring 9, the vibrations and shocks offset each other and dampen by interaction between the anti-vibration steel plates 9b and the anti-vibration rubber plates 9a of the anti- vibration spring 9.
[36] FIG. 7 is a graph illustrating experimental results for comparing the case where the track tension controlling apparatus with the anti- vibration spring 9 is used in a heavy- duty vehicle according to the present invention with the case where a conventional track tension controlling apparatus is used in the heavy-duty vehicle. In FIG. 7, a dashed line indicates the case where the conventional track tension controlling apparatus is used, and a solid line indicates the case where the track tension controlling apparatus of the present invention is used.
[37] Referring to FIG. 7, a vehicle body vibrates less and regularly regardless of start, travel, and stop of the heavy-duty vehicle when the track tension controlling apparatus of the present invention is used in the heavy-duty vehicle. However, the vehicle body vibrates largely and irregularly according to the start, travel, and stop of the heavy-duty vehicle when the conventional track tension controlling apparatus is used in the heavy- duty vehicle.
[38]