JP2009185542A - Construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a construction machine having a vibration damping structure damping the vibration transmitted to a hollow structure without requiring a damping material such as urethane. <P>SOLUTION: This construction machine comprises a vibration damping structure for damping the vibration transmitted to the boom 4 of the hollow structure when an engine, a hydraulic pump, and a heat exchanger are driven during an excavating operation. The vibration damping structure comprises a hole 8a in a partition wall formed in the boom 4 and a cylindrical body 13 which is attached to the side surface 8b of the partition wall 8, which communicates with the hole 8a, and which projects into a space 11. The cylindrical body 13 comprises a hollow cross section of the same shape as the circular hole 8a formed in the side surface 8b of the partition wall 8. The cylindrical body 13 is attached to the partition wall 8 so that the hollow cross section matches the hole 8a. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a construction machine such as a hydraulic excavator provided with a vibration damping structure that includes a hollow structure such as a boom to which vibration is transmitted and that attenuates vibration transmitted to the hollow structure.

There exists a thing shown by patent document 1 as this type of prior art. In this Patent Document 1, a hydraulic excavator is shown as a work machine, that is, a construction machine, and a partition plate that partitions the interior of the arm into three spaces, that is, a partition wall, is provided inside the arm constituting the front working machine of the hydraulic excavator. Two are provided, and between these partition walls, a vibration damping material, such as urethane, that damps air vibrations inside the arm that accompanies the operation of the engine, hydraulic pump, heat exchanger, etc. during operation is filled, and resonance inside the arm There has been disclosed a vibration damping structure which prevents the above. This vibration damping structure suppresses air vibration inside the arm during work, and reduces noise caused by this vibration.
JP 2002-274441 A

  This prior art fills the inside of the arm with urethane or the like, resulting in a large vibration damping structure. In addition, a complicated operation of filling urethane or the like between the partition walls inside the arm is required, and this easily increases the number of steps for manufacturing the vibration damping structure. For these reasons, the vibration damping structure disclosed in the prior art has a problem of high manufacturing costs.

  When considering the recycling of hydraulic excavators in the conventional technology when scrapped, the front work machine including the arm is made of steel, and the damping material filled in the arm is made of urethane or the like, and the materials are different from each other. Therefore, there is a concern that the man-hours required for separation will increase.

  The present invention has been made from the above-described prior art, and the object thereof is to realize a vibration damping structure capable of attenuating vibration transmitted to the hollow structure without requiring a damping material such as urethane. To provide construction machinery.

  In order to achieve this object, a construction machine according to the present invention includes a hollow structure body having a space therein and vibrations transmitted thereto, and a vibration damping structure that attenuates the vibrations transmitted to the hollow structure bodies. In the construction machine provided, the vibration damping structure is characterized by comprising a hole formed in the hollow structure and a cylindrical body connected to the hole and attached to the hollow structure.

  According to the present invention configured as described above, the hollow structure and the cylindrical body can form a resonance box that attenuates air vibration due to resonance without requiring a damping material such as urethane. Therefore, the cylindrical body is closed by preparing the shape and dimensions of the cylindrical body according to the frequency of the natural vibration generated in the closed space where the cylindrical body is placed in advance. Air vibrations in the space can be attenuated, and noise can be reduced. Moreover, since this invention only forms a hole in a hollow structure body and attaches the cylindrical body connected to this hole to a hollow structure body, a structure is simple and it can suppress a manufacturing man-hour.

  Further, in the construction machine according to the present invention, in the above invention, the cylindrical body has a hollow cross section having the same shape as the hole, and the cylindrical body is configured to match the hollow cross section and the hole. It is characterized by being attached to a hollow structure.

  In the construction machine according to the present invention, in the above invention, the hollow structure has a partition that forms a plurality of the spaces therein, the hole is formed in the partition, and the cylindrical body is the partition. It is characterized by being attached to.

  In the construction machine according to the present invention as set forth in the invention described above, the hollow structure body includes a boom or an arm constituting a front work machine.

  Moreover, the construction machine according to the present invention is characterized in that, in the above invention, the hollow structure body is formed of a hollow structure member formed below the operator cab.

  In the present invention, the vibration damping structure that attenuates the vibration transmitted to the hollow structure includes a hole formed in the hollow structure and a cylindrical body that is connected to the hole and attached to the hollow structure. A vibration damping structure capable of attenuating the vibration transmitted to the hollow structure can be realized without requiring a damping material such as, and the configuration of the vibration damping structure is simple and the number of manufacturing steps can be reduced. As a result, it is possible to obtain a construction machine capable of reducing the manufacturing cost of the vibration damping structure as compared with the conventional case.

  The best mode for carrying out the construction machine according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a side view of a hydraulic excavator constituting a first embodiment of a construction machine according to the present invention, FIG. 2 is a view showing a boom provided to the hydraulic excavator according to the first embodiment, and FIG. (B) The figure is an AA cross-sectional enlarged view of (a) figure, (c) The figure is a BB cross-sectional enlarged figure of (a) figure.

  The construction machine according to the first embodiment of the present invention is, for example, a hydraulic excavator. The hydraulic excavator includes, as shown in FIG. 1, a traveling body 1, a revolving body 2 disposed on the traveling body 1, and this The swivel body 2 is provided with a front work machine 3 that is provided so as to be rotatable in the vertical direction and that performs excavation work of earth and sand. The front work machine 3 includes a boom 4 attached to the revolving body 2 so as to be rotatable in the vertical direction, an arm 5 attached to the tip of the boom 4, and a bucket 6 attached to the tip of the arm 5. Yes. The boom 4 and the arm 5 have a space inside, and constitute a hollow structure body to which vibrations generated by driving of an engine, a hydraulic pump, a heat exchanger and the like during excavation work are transmitted.

  As shown in FIG. 2B, for example, the boom 4 constituting the hollow structure is welded to the upper plate 4a, the lower plate 4b, and the upper plate 4a and the lower plate 4b so as to face each other. Side plates 4c and 4d. The upper plate 4a, the lower plate 4b, and the side plates 4c and 4d are made of steel.

As shown in FIG. 2A, the boom 4 has two partition walls 8 and 9 made of steel.
Is provided. By these partition walls 8 and 9, three substantially closed spaces 10, 11 and 12 are formed inside the boom 4.

  The first embodiment includes a vibration damping structure that attenuates vibration transmitted to the boom 4 that forms the hollow structure body when the engine, hydraulic pump, heat exchanger, and the like are driven during excavation work. The vibration damping structure includes a hole formed in the boom 4 and a cylindrical body that communicates with the hole and is attached to the boom 4. For example, a circular hole 8 a is formed in the partition wall 8 of the two partition walls 8, 9 described above, and a cylindrical tubular body 13 made of, for example, a steel material protruding into the space 11 on the side surface 8 b of the partition wall 8. Are welded. The cylindrical body 13 has a hollow section having the same shape as the circular hole 8a formed in the side surface 8b of the partition wall 8, and the cylindrical body 13 is attached to the partition wall 8 so that the hollow section and the hole 8a are aligned. is there.

Also,
S: Cross-sectional area of the hollow section of the cylindrical body 13 C: Sound velocity L: Length of the cylindrical body 13 r: Inner diameter of the cylindrical body 13 La: L + nr (n is a correction coefficient)
V: volume of space 10 f: frequency of natural vibration of space 11
f = (C / 2π) √ (S / (V · La))
In order to satisfy the above relationship, the position of the partition wall 8 and the shape dimension of the cylindrical body 13 are set in advance.

  1st Embodiment comprised in this way attenuate | damps the air vibration by resonance of the space 11 by 10A of structural parts which have the space 10 formed of the partition 8 of the boom 4, and the cylindrical body 13 attached to the partition 8. A resonance box to be formed can be formed. Therefore, when vibrations associated with driving of the engine, hydraulic pump, etc. during excavation work are applied to the boom 4, air vibrations in the closed space 11 in which the cylindrical body 13 is disposed are used as damping materials such as urethane. It can be attenuated without requiring. Thereby, the noise by the vibration transmitted to the boom 4 can be reduced.

  According to the first embodiment, the hole 8a is formed in the partition wall 8 provided in the boom 4 forming the hollow structure, and the cylindrical body 13 communicating with the hole 8a is simply welded to the partition wall 8. The structure of the vibration damping structure is simple, and the number of manufacturing steps can be reduced. As a result, a hydraulic excavator capable of reducing the manufacturing cost of the vibration damping structure can be obtained.

  When recycling the hydraulic excavator, the boom 4, the partition walls 8 and 9 provided inside the boom 4, and the cylindrical body 13 attached to the partition wall 8 are made of steel. There is no need to separate members made of different materials from steel. Therefore, the man-hours required for recycling the hydraulic excavator can be reduced.

  FIG. 3 is a diagram showing a main part of the second embodiment of the present invention. In the second embodiment shown in FIG. 3, the tubular body 15 is inserted into the hole of the partition wall 8 of the boom 4 described above. In the second embodiment, the air vibration of the space 11 is caused by the portion 15a of the cylindrical body 15 in which the side surface 8b of the partition wall 8 protrudes toward the space 11 shown in FIG. 2 and the structural portion 10A of the boom 4 having the space 10. A vibration damping structure is formed, and a portion 15b of the cylindrical body 15 protruding from the side surface 8c of the partition wall 8 toward the space 10 shown in FIG. 2 and a structure portion 11A of the boom 4 having the space 11 A vibration damping structure for attenuating air vibrations in the space 10 is formed. Other configurations are the same as those of the first embodiment.

  The second embodiment configured as described above can attenuate both the air vibration generated in the space 11 of the structural part 11A of the boom 4 and the air vibration generated in the space 10 of the structural part 10A of the boom 4, and is further excellent. The vibration damping function can be secured. Other functions and effects are the same as those of the first embodiment.

  FIG. 4 is a diagram showing a main part of the third embodiment of the present invention. In the third embodiment shown in FIG. 4, one end is welded to the side surface 8 b of the partition wall 8 and the other end is connected to both the hole 8 a of the partition wall 8 provided in the boom 4 and the hole 9 a of the partition wall 9. A tubular body 16 is provided which is welded to the side surface 9 b of the partition wall 9 and is curved so as to follow the shape of the boom 4.

  In the third embodiment, a vibration damping structure that attenuates air vibrations in the space 12 is formed by the tubular body 16 and the structural portion 10A of the boom 4 having the space 10, and the tubular body 16 and the space A vibration damping structure for damping air vibrations in the space 10 is formed by the structural portion 12 </ b> A of the boom 4 having 12. Other configurations are the same as those of the first embodiment.

  3rd Embodiment comprised in this way can attenuate both the air vibration which arises in the space 12 of the structural part 12A of the boom 4, and the air vibration which arises in the space 10 of the structural part 10A, The outstanding vibration damping performance Can be secured. In the third embodiment, although the number of welded portions of the cylindrical body 16 is increased as compared with the first embodiment, a relatively simple configuration can be achieved, and the number of manufacturing steps can be reduced.

  FIG. 5 is a diagram showing a main part of the fourth embodiment of the present invention. In the fourth embodiment shown in FIG. 5, in addition to the configuration of the first embodiment shown in FIG. 2, a hole 9a is formed in the partition wall 9, and the side surface 9b of the partition wall 9 is communicated with the hole 9a. The cylindrical body 17 is welded.

  In the fourth embodiment, a vibration damping structure that attenuates air vibrations in the space 11 is formed by the tubular body 13 and the structural portion 10A of the boom 4 having the space portion 10, and the tubular body 17, A vibration damping structure for attenuating air vibration in the space 11 is formed by the structural portion 12A of the boom 4 having the space 12. Other configurations are the same as those of the first embodiment.

  The fourth embodiment configured as described above can attenuate the air vibration of the space 11 formed in the boom 4 by the two vibration damping structures, and can further secure the vibration damping performance better than that in the first embodiment. it can. Although the fourth embodiment also has a greater number of welded portions of the cylindrical body 17 than the first embodiment, the fourth embodiment can have a relatively simple structure and can reduce the number of manufacturing steps.

  In the first to fourth embodiments, the boom 4 is provided with a vibration damping structure. However, a similar vibration damping structure may be provided on the arm 3.

  6 is a perspective view showing a lower part of a cab constituting a main part of a fifth embodiment of the present invention, FIG. 7 is a plan view of the main part of FIG. 6, and FIG. 8 is a cross-sectional view of the main part of FIG. FIG.

  The fifth embodiment whose main parts are shown in FIGS. 6 to 8 is also the hydraulic excavator shown in FIG. 1, for example. In the third embodiment, the hollow structure constituting the vibration damping structure is provided in the cab 7. It consists of hollow structural members 20 and 21 provided in the revolving frame 2a which is located below and supports this cab 7. These hollow structural members 20 and 21 are made of steel materials having spaces 30 and 31, respectively, as shown in FIGS. For ease of explanation, in FIGS. 6 to 8, the upper portion of the space 22 a is depicted as being open, but actually, the space 22 a is substantially closed by the floor of the cab 7 or the like. It has become.

  In the fifth embodiment, a hole 20 a is provided in the hollow structural member 20, and a cylindrical body 23 made of a steel material communicating with the hole 20 a is welded to the hollow structural member 20. The cylindrical body 23 is located in the space 22a. Further, a hole 21 a is provided in the hollow structural member 21, and a cylindrical body 24 made of a steel material communicating with the hole 21 a is welded to the hollow structural member 21. The cylindrical body 24 is also positioned in the space 22a.

  In the fifth embodiment, the cylindrical body 23 and the hollow structural member 20 having the space 30 form a vibration damping structure that attenuates the air vibration of the space 22 a, and the cylindrical body 24 and the hollow having the space 31 are formed. The structural member 21 forms a vibration damping structure that attenuates air vibration in the space 22a.

  In the fifth embodiment configured as described above, the air vibration generated in the space 22a formed below the cab 7 due to the driving of the engine, the hydraulic pump, etc. during excavation work or the like is caused by two vibration damping structures. Damping can be performed without requiring a damping material such as urethane, and excellent vibration damping performance can be obtained. As a result, noise in the cab 7 can be reduced. In addition, the hollow structural members 20 and 21 are provided with holes 20a and 21a, respectively, and the cylindrical bodies 23 and 24 are simply welded, so that the number of manufacturing steps can be reduced. Therefore, substantially the same operational effect as in the first to fourth embodiments described above can be obtained.

  FIG. 9 is a plan view showing the main part of the sixth embodiment of the present invention. FIG. 9 is drawn corresponding to FIG. 7 according to the fifth embodiment described above. In the sixth embodiment shown in FIG. 9, a partition wall 25 is provided inside the hollow structural member 20. Holes 20b and 20c are provided in the structure portion 20A having the space 26 formed by the partition wall 25 and the structure portion 20A having the space 27, respectively. In addition, a cylindrical body 28 made of a steel material is welded to the structural portion 20 </ b> A of the hollow structural member 20 so as to communicate with the hole 20 b and project into a substantially closed space 22 b formed below the cab 7. Further, as described above, the cylindrical body 29 made of a steel material is welded to the hollow structural member 20 so as to protrude into the space 22a formed below the cab 7 as described above.

  In the sixth embodiment, a vibration damping structure that attenuates air vibration in the space 22b is formed by the cylindrical body 28 and the structural portion 20A of the hollow structural member 20 having the space 26, and the cylindrical body 29 and the space A vibration attenuating structure for attenuating the air vibration in the space 22a is formed by the structural portion 20B of the hollow structural member 20 having 27.

  6th Embodiment comprised in this way can attenuate the air vibration which arises in the space 22a, 22b formed under the cab 7, and the outstanding vibration damping performance is obtained. In addition, each vibration damping structure has a relatively simple configuration, and can reduce the number of manufacturing steps.

  FIG. 10 is a plan view showing an essential part of a seventh embodiment of the present invention. FIG. 10 is also drawn corresponding to FIG. 7 according to the fifth embodiment described above. In the seventh embodiment shown in FIG. 10, a hollow structure member 20 is provided with a hole 20d, communicates with the hole 20d, protrudes into a space 22b formed below the cab 7, and a cylindrical body 32 made of steel is provided. It is welded to the hollow structural member 20. Further, a hole 21 a is provided in the hollow structural member 21, communicates with the hole 21 a, protrudes into a space 22 a formed below the cab 7, and a tubular body 33 made of steel is welded to the hollow structural member 21. .

  In the seventh embodiment, the cylindrical body 32 and the hollow structural member 20 having the space 30 form a vibration damping structure that attenuates the air vibration of the space 22 b, and the cylindrical body 33 and the hollow having the space 31 are formed. The structural member 21 forms a vibration damping structure that attenuates air vibration in the space 22a. The seventh embodiment configured as described above can also obtain the same operational effects as the sixth embodiment described above.

  In addition, although the shape of the hole provided in the hollow structure body provided in each embodiment mentioned above, for example, the hole 8a of the partition 8 in 1st Embodiment, etc. is made circular, this invention makes the hole 8a etc. in this way. The shape is not limited to a circular shape, and may be a square shape. Moreover, you may comprise the cylindrical body attached to a hollow structure according to this by what the hollow cross section is formed in square shape.

It is a side view of the hydraulic excavator which comprises 1st Embodiment of the construction machine of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the boom with which the hydraulic excavator which concerns on 1st Embodiment is equipped, (a) A figure is a side view, (b) A figure is an AA cross-sectional enlarged view of (a) figure, (c) A figure is (a). It is a BB cross-sectional enlarged view of a figure. It is a figure which shows the principal part of 2nd Embodiment of this invention. It is a figure which shows the principal part of 3rd Embodiment of this invention. It is a figure which shows the principal part of 4th Embodiment of this invention. It is a perspective view which shows the lower part of the cab which comprises the principal part of 5th Embodiment of this invention. FIG. 7 is a plan view of a cross-section of the main part of FIG. 6. FIG. 7 is a side view of a cross section of the main part of FIG. 6. It is a top view which shows the principal part of 6th Embodiment of this invention. It is a top view which shows the principal part of 7th Embodiment of this invention.

Explanation of symbols

2 Revolving body 2a Revolving frame 3 Front work machine 4 Boom (hollow structure)
5 Arm (hollow structure)
7 cab 8 partition 8a hole 8b side 8c side 9 partition 9a hole 9b side 10 space 10A structure part 11 space 11A structure part 12 space 12A structure part 13 cylindrical body 15 cylindrical body 15a part 15b part 16 cylindrical body 17 20 Hollow structure member (hollow structure)
20A structure part 20B structure part 20a hole 20b hole 20c hole 20d hole 21 hollow structure member (hollow structure)
21a hole 22a space 22b space 23 cylindrical body 24 cylindrical body 25 partition wall 26 space 27 space 28 cylindrical body 29 cylindrical body 30 space 31 space 32 cylindrical body 33 cylindrical body

Claims (5)

In a construction machine provided with a vibration damping structure that has a space inside and includes a hollow structure body that can transmit vibration, and that attenuates the vibration transmitted to the hollow structure body.
2. The construction machine according to claim 1, wherein the vibration damping structure includes a hole formed in the hollow structure and a cylindrical body connected to the hole and attached to the hollow structure. In the construction machine according to claim 1,
The tubular body has a hollow section having the same shape as the hole, and the tubular body is attached to the hollow structure body so that the hollow section and the hole coincide with each other. In the construction machine according to claim 1,
The hollow structure has a partition that forms a plurality of the spaces therein, the hole is formed in the partition, and the cylindrical body is attached to the partition. In the construction machine according to claim 1,
The construction machine according to claim 1, wherein the hollow structure includes a boom or an arm constituting a front work machine. In the construction machine according to claim 1,
The construction machine according to claim 1, wherein the hollow structure is formed of a hollow structure member formed below the cab.

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