JP2012189198A - Protective cover of hydraulic piping - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protective cover, which is detachably mounted on a hose that constitutes hydraulic piping already assembled in a prescribed machine, which effectively protects the hose, which prevents oil leakage to the outside even when the hose is damaged, and which allows rapid and easy detection of the damaged hose.SOLUTION: A protective cover 30 comprises a cover body 31 formed of a flexible sheet member and mounted so as to cover an outer circumference of a hose 17b. Both of first and second cover sheets 31a, 31b constituting the cover body 31 are provided with surface fasteners 32 in both side parts, to be fixed to each other while the cover is applied on the hose 17b. A mounting part 33 provided in both ends of the cover body 31 is detachably fixed to a connection port 18 by use of a surface fastener. A bellows part 37 that expands when oil leaks from the hose 17b is mounted between the first cover sheet 31a and the attaching part 33.

Description

  The present invention is constructed such that a hydraulic pipe is routed, such as a hydraulic construction machine, and at least a part of the hydraulic pipe is mounted on a machine configured with a hose having flexibility in a bending direction. The present invention relates to a protective cover for hydraulic piping for protecting the hose to be used.

  As an example of the hydraulic construction machine, there is a hydraulic excavator shown in FIG. The hydraulic excavator is configured by connecting an upper swing body 3 to a lower traveling body 1 through a swing device 2, and a frame 3a of the upper swing body 3 includes a cab 4 and a building 5 constituting a machine room. And a working machine 10 for excavating earth and sand.

  The work machine 10 includes a boom 11 provided on the frame 3 a of the upper swing body 3 so as to be able to be lifted and lowered, an arm 12 connected to the tip of the boom 11 so as to be rotatable in the vertical direction, and a tip of the arm 12. This is generally composed of a bucket 13 as a front attachment provided. A link mechanism 14 is interposed between the arm 12 and the bucket 13, and the movement of the joint is performed by operating the link mechanism 14.

  In order to drive the boom 11, the arm 12, and the bucket 13 that constitute the work implement 10, a boom cylinder 11a, an arm cylinder 12a, and a bucket cylinder 13a that are hydraulic cylinders are provided. A pair of hydraulic pipes are connected to these hydraulic cylinders. A pair of hydraulic piping in the hydraulic cylinder extends into the building 5 and is connected to a control valve provided in the building 5. The piping from the control valve is connected to a hydraulic pump and a hydraulic oil tank. Therefore, by switching the control valve, the flow of hydraulic oil is controlled and the hydraulic cylinder is driven. The hydraulic cylinder constitutes a hydraulic actuator for driving each part of the work machine 10 together with the hydraulic motor. Since the control valve, hydraulic pump, and hydraulic oil tank are well known in the art, illustration and description are omitted.

  As an example of the structure for routing the hydraulic piping to the hydraulic actuator, FIG. 2 shows the configuration of the connecting portion of the hydraulic piping to the arm cylinder 12a. In this case, the hydraulic piping is routed along the back surface of the boom 11. A pair of brackets 15, 15 are provided on the back surface of the boom 11, and the base end portion of the arm cylinder 12 a is rotatably supported by the bracket 15 using a pin 16. One of the two pipes connected to the arm cylinder 12a is connected to an end portion on the cylinder bottom side, and the other end is connected to an end portion on the rod outlet side.

  The arm cylinder 12a is driven so that its rod is extended or contracted. At this time, the base end portion of the arm cylinder 12a rotates about the pin 16 as a result. The pipe becomes bent. Therefore, the hydraulic piping must be flexible in the bending direction. However, from the viewpoint of strength and durability, it is desirable that the hydraulic piping is composed of a rigid member, particularly a metal pipe. Therefore, as shown in FIG. 2, a portion of the hydraulic piping 17 that does not bend, that is, a portion that extends along the rear surface of the boom 11, is constituted by a pipe 17a, and is near the bottom side end of the arm cylinder 12a. Up to this point, the hose 17b is configured to be connected to the arm cylinder 12a, and the connecting portion to the rod lead-out side end is again configured with the pipe 17a. For this purpose, a connection port 18 is provided at the end of the pipe 17, a base 19 is provided at both ends of the hose 17b, and a connection port 18 is also provided at the pipe connection at the bottom end of the arm cylinder 12a. The bases 19 at both ends of the hose 17b are connected to the pipe 17a and the connection port 18 of the arm cylinder 12a. The structure of the pipe connection part by the above system is disclosed by patent document 1, for example. In addition, in patent document 1, although it has the connection structure of the piping in a boom foot part, the connection part of the hydraulic piping 17 to the arm cylinder 12a is also the same.

  By the way, the hose 18 is repeatedly bent, and when it collides with another object, there is a risk of causing damage such as cracking or breaking. Similarly to the arm cylinder 12a, the hydraulic cylinders connected to the bucket cylinder 13a and further to the boom cylinder 11a, the hydraulic oil flows in these hydraulic pipes 17, and in particular, the high-pressure oil applied by the hydraulic cylinder drive pressure flows. From this, when the hose 17a is damaged, the hydraulic oil that has become high pressure will be ejected from the damaged part, and as a result, the hydraulic oil will be scattered around and the soil and the like will be contaminated. You will have to clean over a wide area to remove the oil.

  In order to prevent the occurrence of the above situation, as shown in Patent Document 2, for example, it is conceivable to form hydraulic piping from double flexible tubes of an inner tube and an outer tube. However, when the flexible pipe is constituted by the double pipe, when the inner pipe is damaged, it cannot be detected that the outer pipe is damaged. In Cited Document 3, a method and apparatus for detecting liquid leakage in a double pipe is proposed. That is, the inner pipe is covered with a protective pipe, and air is supplied from one end to the other end between the liquid feeding pipe and the protective pipe, and the pressure is detected on the other end. By connecting the means and detecting a change in pressure by the pressure detecting means, the liquid leakage can be detected.

JP 2000-219933 A JP-A-5-272666 JP 2008-208877 A

  Here, in patent document 2 and patent document 3 mentioned above, what was previously comprised as a double pipe is used as piping. In order to detachably connect the pipe 17a and the hose 17b as in the hydraulic pipe 17 described above, the connection port 18 and the base 19 are screwed together in consideration of the simplification of the configuration. For this purpose, the connection port 18 and the base 19 must be exposed to the outside. On the other hand, when a protective cover is attached to the hose 17b, the protective cover should cover at least the base 19 and preferably the connection port 18 on the side of the pipe 17a in order to fully function as a protective cover. There must be.

  From the above, when the connection between the pipe 17a and the hose 17b is a screw connection between the connection port 18 and the base 19, the connection port 18 and the base 19 must be exposed to the outside. It is not preferable to cover the part with a protective cover. Therefore, as in Patent Document 2 and Patent Document 3, what is assembled in advance as a double pipe cannot be used for detachably connecting the hose to the pipe, or at least the simplicity of the configuration, etc. From the viewpoint of, it is not preferable.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a protective cover for a hydraulic pipe that can be easily attached and detached after the hose and pipe constituting the hydraulic pipe are assembled and joined in the machine. Is to provide.

  In order to achieve the above-mentioned object, the present invention constitutes hydraulic piping and is provided so as to be bridged between mutually movable parts, and both ends are detachably connected to a connection pipe of a metal pipe or hydraulic equipment. A protective cover that is mounted on a flexible hose, comprising a flexible sheet member, and is attached to cover the outer periphery of the hose; A side connecting portion provided on both side portions, in a state where the hose is housed in a cylindrical shape, and detachably fixed to the caps at both ends of the hose or the connection port portion to which both the caps are connected; It is characterized by comprising.

  In the hydraulic piping, for example, in the hydraulic piping connecting the hydraulic pump and the hydraulic cylinder, mutually movable parts, for example, between the frame of the upper swing body of the excavator and the boom, between the boom and the arm, Bendable parts between the bucket, between the boom and arm cylinder, between the arm and bucket cylinder, etc. Therefore, the hydraulic piping is constituted by a flexible hose. On the other hand, since it is not required to be able to bend at the position where the part of the wall surface constituting the boom or arm is extended among the hydraulic pipes, the hydraulic pipes are configured with metal pipes. One end of the hose is connected to a metal pipe, and the other end is directly connected to a hydraulic device such as a hydraulic cylinder, or is connected between front and rear metal pipes and may be further connected between hydraulic devices. For this purpose, caps are provided at both ends of the hose, and connection ports are provided in metal pipes and hydraulic equipment connected to these caps, and these caps and the connection ports are normally detachably connected.

  Of the hydraulic piping routed as described above, at least a portion of the hose is protected by covering with a protective cover. The protection is to prevent the hose from being broken, cracked or broken by an excessive external force acting on the hose when it collides with an obstacle or a flying object. Further, in the case of a construction machine such as a hydraulic excavator that operates outdoors, it is effective for preventing deterioration of the hose by irradiating sunlight.

  The hose is covered with a protective cover, but the hose is covered with the caps at both ends of the hose being connected to the end of the metal pipe constituting the hydraulic piping or the connecting port provided in the hydraulic equipment. For this purpose, the protective cover is composed of a cover body made of a synthetic resin sheet having flexibility, and is covered so as to wrap an existing hose, and both sides of the cover body are connected to form a cylindrical shape. To. For this purpose, a side connecting portion is formed on the side of the cover body. The fixing by the side connecting portion is easy to attach and detach, and has an internal sealing property in the mounted state. For this purpose, it is desirable to use surface fasteners or line fasteners. Of course, as a configuration of the side connecting portion, other than these, for example, adhesion or sewing can be used.

  Both ends of the cover main body are fixed to the connection port portion constituting the end portion of the metal pipe to which the base is connected or the base portion at the tip of the hose. Here, from the viewpoint of protecting the entire hose, it is desirable that the hose extends to the connection port and is fixed to the connection port. The side connecting portion can be extended to the position of the fixing target portion consisting of a base or a connecting port portion at both ends of the cover body, or can be configured as an attaching portion independent of the side connecting portion. And since this attachment part must also be detachable, you may make it have the attachment / detachment mechanism similar to a side part connection part.

  In any case, it is necessary to seal not only the side connecting part that connects both sides of the cover body that houses the hose, but also the part to be fixed to the fixing target part such as the base and the connecting port part. is there. Although tightness can be secured by strongly tightening the fixing target part, when the fixing target part is not a cylindrical shape such as a hexagon nut, it is not advantageous in terms of ensuring the sealing performance. Therefore, in this case, a sealing member having cushioning properties such as rubber can be interposed between the fixing target portion and the cover main body. By making the inner surface shape of the sealing member coincide with the outer surface shape of the portion to be fixed and making the outer surface cylindrical, the sealing property of this part can be ensured.

  Although the protective cover is configured as a cylindrical sheath member in which the hose is accommodated, the protective cover can have an additional function. One of these additional functions is an oil leak detection function. The hose is a high part such as between the frame of the upper swing body of the excavator and the boom, between the boom and the arm, between the arm and the bucket, between the boom and the arm cylinder, between the arm and the bucket cylinder, etc. In place. Therefore, when the hose is damaged and an oil leak occurs, it may be difficult to detect the oil leak location. High-pressure oil flows in the hose, and the hose is sealed by the protective cover, so the pressure inside the protective cover increases rapidly. Therefore, when there is a pressure increase in the protective cover, at least a part of the protective cover is configured to expand. For example, if the bellows part is provided in a part and the bellows part is assembled in a contracted state, the bellows part expands due to an increase in internal pressure. Therefore, if the expansion of the bellows part can be detected, for example, if coloring that is visually stimulated by the bellows part is performed, the visual recognition from the outside becomes easy. In addition, high-pressure oil is not ejected, and hydraulic oil having a relatively low pressure may gradually flow out. Also in this case, since the internal volume of the protective cover increases due to the outflow of oil, the bellows part also expands.

  When oil flows out, the pressure inside the protective cover rises and the volume increases. Therefore, it is necessary to keep the inside of the protective cover sealed. However, since oil is a viscous fluid, the volume of the bellows part can be reduced when oil flows out of the hose without securing a special high level of airtightness. Since it expands, it can prevent leaking outside from the protective cover. In addition, the cover body is always compact with a reduced diameter, such as an oil sump bag. When there is oil leakage from the hose, an external flexible oil leakage prevention function can be achieved by providing an expanding flexible bag. Definitely demonstrate. Furthermore, if an absorbent mat that absorbs oil is provided on the inner surface of the cover body, or an oil receiving pocket is provided, or if both an absorbent mat and an oil receiving pocket are provided, the exterior of the oil More effective to prevent spillage. In addition, when using hook-and-loop fasteners, if a gelling agent that gels when oil is absorbed is applied to the overlapped portion, when internal oil leakage occurs, the sealing property due to gelation becomes higher and the external Oil leakage can be prevented more reliably.

  In order to improve the weather resistance of the hose, it is desirable that the outer surface of the protective cover is colored in a silver system that efficiently reflects sunlight or the like. Moreover, it can also be set as a heat insulation part by forming a clearance gap between a protective cover and a hose. For this purpose, the diameter of the protective cover is made larger than the diameter of the hose. In order to make the gap between them substantially constant over the entire length, a plurality of spacers may be attached to the inner surface of the cover body of the protective cover.

  By configuring the protective cover as described above, the hoses constituting the hydraulic piping can be effectively protected, and can be easily attached to or detached from the hoses in the hydraulic piping already incorporated in the machine.

It is a front view of a hydraulic excavator as an example of a machine provided with hydraulic piping. FIG. 2 is a configuration explanatory diagram showing hydraulic piping to an arm cylinder in the hydraulic excavator of FIG. 1. It is a front view which shows the state which isolate | separated the connection part of the pipe and hose which comprise hydraulic piping. It is a front view which shows the state which isolate | separated the connection part of the pipe and hose which comprise hydraulic piping. It is a front view which shows the state which attached the protective cover in the 1st Embodiment of this invention to the hose in hydraulic piping. It is a front view shown in the state where the protective cover of Drawing 5 was developed. It is AA sectional drawing of FIG. It is a principal part enlarged view which shows the state which the bellows part in the protective cover expanded. It is composition explanatory drawing of the annular | circular shaped flexible sheet | seat which forms a bellows part. It is a front view shown in the state where a protective cover showing a 2nd embodiment of the present invention was developed. It is a front view which shows the state which mounted | wore the hose with the protective cover of FIG. It is composition explanatory drawing of the line fastener which comprises the side part connection part in the protective cover in the 2nd Embodiment of this invention. It is sectional drawing of the base end part of the protection cover in a mounting state. It is BB sectional drawing of FIG. It is a figure similar to FIG. 11 which shows the modification in the 2nd Embodiment of this invention. It is sectional drawing of the mounting part to the hose of the protective cover which shows the 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Here, the protective cover for the hydraulic piping shown in the present embodiment is made of metal provided on the back surface of the boom 11 shown in FIG. 2 in the working machine 10 of the hydraulic excavator shown in FIG. The hose 17b of the hydraulic pipe 17 is protected from the pipe 17a and the hose 17b having the base 19 connected to the connection port 18 of the pipe 17a. The mounting position of the protective cover is not limited to this, and the protective cover can be used for protecting a hose in any hydraulic piping provided in the machine.

  Therefore, FIG. 3 and FIG. 4 show the configuration of the connecting portion between the pipe 17a and the hose 17b. FIG. 3 shows a state where the pipe 17a and the hose 17b are separated, and FIG. 4 shows a connection state between the pipe 17a and the hose 17b. Thus, in order to connect the pipe 17a and the hose 17b, the threaded portion 20 is formed on the outer peripheral surface of the tip portion of the pipe 17a, and the locking nut 21 is screwed into the threaded portion 20. The connection port part 18 is comprised from these. On the other hand, the base 19 of the hose 17b includes a hose connecting portion 22 provided with a nut-like protruding portion 22a and a nut portion 23 rotatably connected to the tip of the hose connecting portion 22.

  Therefore, the nut portion 23 constituting the base 19 of the hose 17b is screwed to the tip end portion of the screw portion 20 of the pipe 17a, and the lock nut 21 provided on the pipe 17a side is screwed to contact the end surface of the nut portion 23. By moving to the contact position, the pipe 17a and the hose 17b are connected. The other end of the hose 17b is connected to a connection port 18 provided in the arm cylinder 12a. This connection port 18 has the same configuration as the connection port 18 provided at the tip of the pipe 17a, and thus has been described above. The other end of the hose 17b is connected to the arm cylinder 12a in the same procedure as in FIG.

  The protective cover 30 according to the first embodiment of the present invention is mounted so as to cover the outer periphery of the hose 17b assembled in this way. That is, as shown in FIG. 5, the protective cover 30 extends beyond the positions of the caps 19 and 19 at both ends of the hose 17b to the position of the nut 21 constituting the connection port 18 provided in the pipe 17a and the arm cylinder 12a. It extends and is fixed to the outer surface of the nut 21.

  As shown in FIGS. 6 and 7, the protective cover 30 has a cover main body 31 having a predetermined width as a whole and made of a sheet member slightly longer than the hose 17 b, and both sides of the cover main body 31. The hook-and-loop fastener 32 is fixed to a predetermined width. On one side, a surface fastener 32 is provided on the front surface side, and on the other side, a surface fastener 32 is provided on the back surface side. Therefore, the hose 17b is placed inside, the hose 17b is wrapped, the hook-and-loop fasteners 32 are brought into contact with each other, and the pressing force is applied, whereby the protective cover 30 is mounted on the hose 17b. Become. Accordingly, these surface fasteners 32, 32 constitute a side connecting portion.

  Attachment portions 33 are fixed to both ends of the cover body 31, and hook and loop fasteners 34 are provided on both sides of the attachment portion 33. The attachment portion 33 is attached so as to surround the outer peripheral surface of the nut 21 constituting the connection port portion 18, and is fixed by abutting and pressing the surface fasteners 34 provided on both sides. In FIG. 6, the connecting portion between the attachment portion 33 and the cover body 31 is shown expanded.

  The cover main body 31 is divided into a first cover sheet 31a and a second cover sheet 31b. These first and second cover sheets 31a and 31b are at least waterproof, such as cloth and soft resin. It is comprised from the sheet-like member which has flexibility. Moreover, the attaching part 33 is also comprised from the member similar to the 1st, 2nd cover sheets 31a and 31b. And between the 1st, 2nd cover sheets 31a and 31b and between the attachment parts 33 is fixed by means, such as sewing. Here, the first cover sheet 31a is attached to the second cover sheet 31b, and the second cover sheet 31b is attached to the attachment portion 33 by so-called gather sewing so as to attach curved folds. Yes. The second cover sheet 31b is provided with an oil absorbing mat 35 fixed thereto, and oil receiving pockets 36 are provided in two upper and lower stages at positions close to the oil absorbing mat 35, respectively.

  The second cover sheet 31b and the attachment portion 33 are directly connected, but the first cover sheet 31a is not directly connected to the attachment portion 33, and a bellows portion 37 is interposed therebetween. is doing. The bellows portion 37 functions as an oil leak detection portion. The bellows portion 37 is held in a contracted state in the assembled state as shown in FIG. 5, and when the internal volume is increased, FIG. It expands so as to expand up and down as shown in FIG. As shown in FIG. 9A, the bellows portion 37 is composed of a plurality of annular flexible sheets 38 that are stacked one above the other, and the annular flexible sheets 38, 38 arranged one above the other are sequentially arranged. The outer circumferential side and the inner circumferential side are sewn together, but this annular flexible sheet 38 is provided with a cut 38a in one radial direction. A connecting tongue 38b extends from one side, and the connecting tongue 38b is inserted between the upper and lower annular flexible sheets 38 as shown in FIG. 9B. ing. As a result, it is possible to open and close left and right with the cut line 38a as a boundary. By inserting the connecting tongue piece 38b between the upper and lower annular flexible sheets 38, 38, the bellows portion 37 is assembled, Sealing is ensured.

  This embodiment is configured as described above, and the hose 17b is provided between the pipe 17a provided on the back surface of the boom 11 in the work machine 10 and the connection port 18 provided at the end of the arm cylinder 12a. By connecting the caps 19, 19 at both ends, a hydraulic pipe 17 to the arm cylinder 12a is formed. In this manner, the protective cover 30 is attached to the hose 17b with the hydraulic pipe 17 provided at a predetermined position.

  For this purpose, as shown in FIG. 6, the first and second cover sheets 31a and 31b constituting the cover body 31 and the attachment portions 33 provided at both ends thereof are planarized. The bellows portion 37 is formed so that the portion of the cut 38a is opened to the left and right, and is wound around the outer peripheral portion of the hose 17b, and the connecting tongue 38b is inserted between the upper and lower annular flexible sheets 38, 38. Thus, the hose 17b is surrounded to construct the bellows portion 37, and in this state, the attachment portions 33, 33 provided at both ends of the cover body 31 are provided on the pipe 17a and the arm cylinder 12a, respectively. The hose 17b is wrapped around the connection ports 18 and 18, and the hose 17b is wrapped with the cover main body 31, and the hook and loop fasteners 34 provided on both sides thereof are overlapped and fixed to each other. As a result, the hose 17 b is covered with the protective cover 30, and both ends of the protective cover 30 extend to the position of the connection port 18.

  As a result, the outer peripheral portion of the hose 17b is completely covered by the protective cover 30 over its entire length and is not exposed to the outside. In addition, the portion of the cover main body 31 and the portion of the attachment portion 33 are detachably fixed by the surface fasteners 32 and 34, and the internal hose 17b is sealed. Although the site | part of the bellows part 37 has the cut | interruption 38a, the clearance gap is obstruct | occluded by the tongue piece 38b for connection. Therefore, the inside of the protective cover 30 is kept sealed. However, the inside of the protective cover 30 is not completely airtight. When the arm cylinder 12a is actuated and rotated around the pin 16, the inside of the protective cover 30 is somewhat expanded and contracted. Exhaust and intake can be performed. The inside of the protective cover 30 is liquid-tight, and particularly hermeticity is obtained to the extent that hydraulic oil having a predetermined viscosity does not leak.

  When the arm cylinder 12a is repeatedly operated, a bending force acts on the hose 17b accordingly, and stress is concentrated particularly on the connection portion of the hose 17b to the base 19 to cause a crack or the like. There is. As a result, oil leaks from the hose 17b. In particular, when high pressure oil is supplied to the arm cylinder 12a, if the hose 17b is broken, high pressure hydraulic oil is ejected. However, since the hose 17b is covered with the protective cover 30, there is no risk of oil leakage to the outside, and the surroundings are not soiled with oil. In particular, since the protective cover 30 covers not only the hose 17b but also the connection port 18 to which both ends of the hose 17b are connected, the countermeasure against oil leakage is almost complete.

  Further, since the oil absorbing mat 35 is mounted inside the protective cover 30, oil leaking from the hose 17b is absorbed by the oil absorbing mat 35, and an oil receiving pocket 36 is also provided. The oil receiving pocket 36 exhibits a dam effect and can prevent leakage oil from leaking outside.

  As countermeasures against oil leakage, the oil staying in the protective cover 30 is prevented from leaking to the outside by means of hook-and-loop fasteners and by the oil absorbing mat 35 and the oil receiving pocket 36. However, a more advanced oil leakage function is demonstrated. For this purpose, the surface fasteners 32 and 34 are impregnated with a gelling agent in advance. Here, the gelling agent is preferably, for example, poly (p-oxybenzoyl), poly (2-oxy-6-naphthoyl), poly (oxymethylene) or the like. When the surface fasteners 32 and 34 are impregnated with the gelling agent in this way, when the oil leakage occurs in the hose 17b, the gelling agent becomes a gel state, and the overlapping portions of the surface fasteners 32 and 34 are overlapped. The hermeticity becomes higher.

  As described above, if oil leakage occurs in the hose 17b, it needs to be replaced. This hose 17b must be replaced as quickly as possible. However, since the arm cylinder 12a is mounted at a high place, it may be difficult to confirm from the outside whether or not the hose 17b is damaged. Here, when high-pressure oil is ejected from the hose 17b, the internal pressure of the protective cover 30 covering the hose 17b rises and tends to expand. A bellows portion 37 that can be expanded and contracted is provided in a part of the protective cover 30. As shown in FIG. 5, the bellows portion 37 is always in a state where the annular flexible sheet 38 substantially overlaps vertically, and when the internal pressure of the protective cover 30 rises, the bellows portion 37 moves up and down. Is expanded to the state shown in FIG. 8, and its outer surface is exposed. Accordingly, by coloring the outer surface of the annular flexible sheet 38 constituting the bellows portion 37 in a strongly stimulating color, the visibility of the bellows portion 37 with respect to expansion is increased, and the hose 17b is broken. It becomes possible to recognize quickly and accurately. Further, even when a low pressure oil leak occurs, the internal space of the protective cover 30 decreases due to the oil leak and the pressure rises, so that the bellows portion 37 also expands and the breakage of the hose 17b is detected. can do.

  The protective cover 30 is not only for preventing the oil from splashing around when the hose 17b is broken, but also when the protective cover 30 collides with a structure, rubble, trees, etc. Thus, a buffering function that prevents an impact from being applied to the hose 17b is exhibited. As a result, damage caused by the hose 17b colliding with other objects can be prevented. The hose 17b is generally black, and generally the main raw material is rubber. Moreover, since the hydraulic excavator is operated outdoors, the hose 17b is exposed to sunlight and the deterioration proceeds. However, since the hose 17b is covered with the protective cover 30, sunlight is not directly irradiated. Therefore, the weather resistance is improved, the degree of deterioration can be alleviated, and the life can be extended. The protective cover 30 is preferably excellent in light reflectivity, and for this purpose, it is desirable to have a silver color tone.

  Next, FIGS. 10 to 14 show a second embodiment of the present invention. As shown in FIGS. 10 and 11, the cover body 41 of the protective cover 40 is made of a rectangular silver-based synthetic resin sheet material, as in the first embodiment. The cover main body 41 is composed of a single sheet. As shown in FIG. 10, the cover main body 41 is provided with fastener pieces 42a and 42b on both sides thereof. As shown in FIG. When these are connected in a cylindrical shape, a line fastener 42 is obtained. As a result, the cover main body 41 becomes a substantially cylindrical sheath member, and a space in which the hose 17b can be accommodated is formed.

  Here, the wire fastener 42 does not rub against the hose 17b or external members when the element is made of metal, regardless of whether a synthetic resin element is used. In order to achieve this, as shown in FIG. 12, a cover tape 43 is fixed to both fastener pieces 42a and 42b, and the outer surface side is directed from one fastener piece 42a to the other fastener piece 42b. In addition, a cover tape 43 is fixed to the inner surface of the other fastener piece 42b from the other fastener piece 42b toward the one fastener piece 42a. The cover tape 43 moves the meshing portion of the metal element in the wire fastener 42 up and down. It is fastened so that it may be pinched from. Note that the covering tape 43 is indicated by a virtual line in FIGS. 10 and 11.

  The cover main body 41 has one or more openings 44 at one end thereof, and the opening 44 is sealed by mounting a flexible sheet 45 that can be expanded and contracted. When both sides of the cover body 41 are closed by the wire fastener 42 and formed into a cylindrical shape, an annular interior is formed between the outer surface of the hose 17b and the inner surface of the cover body 41 as shown in FIGS. A space is formed. And the part of the one end side in the cover main body 41 is held in a state where it does not protrude from the outer surface of the cover main body 41 as shown by the solid line when the internal space is in a normal pressure state. The flexible sheet 45 expands outward and swells as indicated by phantom lines in the figure.

  Here, the flexible sheet 45 bulges when hydraulic fluid flowing in the hydraulic pipe 17 leaks between the outer surface of the hose 17b and the inner surface of the cover body 41, and the hose 17b is damaged. When hydraulic oil leaks into the annular inner space between the hose 17b and the cover body 41, the flexible sheet 45 swells to function as an oil reservoir. As a result, the leaked oil is not scattered outside. Further, when the flexible sheet 45 swells, it can be visually recognized from the outside, and therefore oil leakage can be detected.

  The portion of the protective cover 40 to which the flexible sheet 45 is attached is preferably positioned below from the viewpoint of oil sump. In the hydraulic excavator in FIG. 1, a state where the boom 11 is lowered is shown, but this is a resting posture of the hydraulic excavator. When the excavator is operated to perform work such as excavation of earth and sand, the boom 11 is generally in a position raised from the horizontal. At this time, the hose 17b constituting the hydraulic pipe connected to the arm cylinder 12a has a connection side to the arm cylinder 12a on the upper side, and a pipe 17a extending on the back surface of the boom 11 is located on the lower side. Become. Accordingly, when the protective cover 40 is attached to the hose 17b of the hydraulic pipe 17 shown in FIG. 2, the flexible sheet 45 is attached so as to be positioned on the connection portion side to the pipe 17a. In the resting position shown in FIG. 1, the side on which the flexible sheet 45 serving as the oil reservoir is provided may be upward, but in the resting position, high-pressure oil does not flow inside the hose 17b. Even if the hose 17b is damaged, if the damage is slight, oil does not leak out of the hose 17b.

  Thus, it is necessary to seal the connection part to the pipe 17a of the protective cover 40 which becomes a lower position in the operating state so that there is no oil leakage. Therefore, the mounting portion of the protective cover 40 to the pipe 17a and preferably the mounting portion to the arm cylinder 12a are also configured as shown in FIGS. That is, the outer surface of the lock nut 24 attached to the connection port 18 is hexagonal, and a seal member 46 made of an elastic member such as rubber is attached to the lock nut 24. The seal member 46 includes an end plate portion 46a and a peripheral body portion 46b that are integrally provided. The end plate portion 46a has a circular hole 47 that is the same as or slightly smaller than the outer diameter of the hose 17b. The peripheral body portion 46b is a hexagonal portion whose inner peripheral surface can be in close contact with the outer surface of the lock nut 24, and the outer surface has a cylindrical shape.

  The seal member 46 is formed with a cut 48 extending from the end plate portion 46a to the end of the peripheral body portion 46b, and can be opened to the left and right by the cut 48, and the pipe 17a has a hole 47 in the end plate portion 46a. Can be attached to the pipe 17a. The end plate portion 46a is fixedly held at that position by contacting the end surface portion of the lock nut 24. Further, the outer surface of the seal member 46 has a diameter slightly larger than the inner surface of the end portion of the protective cover 40 when the protective cover 40 is formed into a cylindrical shape, so that the protective member 40 is protected when the wire fastener 42 is closed. The end portion of the cover 40 is firmly fixed to the hydraulic pipe 17 and the end portion is sealed so as not to leak oil.

  With this configuration, even if any part of the entire length of the hose 17b including the connecting portion to the base 19 is damaged and internal hydraulic fluid leaks out, the hose 17a and the protective cover 40 It will be hold | maintained inside the annular | circular shaped clearance gap between. When the inside of the annular gap is filled with leaked hydraulic oil, the flexible sheet 45 is pushed and bulges outward to form an oil reservoir, thus preventing external leakage of hydraulic oil. can do. Here, leakage of hydraulic oil due to breakage of the hose 17b occurs when the inside of the hose 17b is in a high pressure state. When the pressure in the hose 17b is reduced to the tank pressure, There is almost no oil leakage from the damaged part. That is, the amount of hydraulic oil leakage is limited, and therefore the size of the opening 44 and the size of the opening 44 that can be attached to the opening 44 based on the amount of hydraulic oil that leaks to the outside when the hose 17b is damaged in a normal state. What is necessary is just to select the characteristic etc. of the flexible sheet | seat 45. FIG.

  The protective cover 40 protects the hose 17b from being damaged, and prevents leakage of external oil even if the hose 17b is damaged. As already described, the hose 17b is provided in a movable part of the hydraulic piping to provide flexibility in the bending direction. At this time, the protective cover 40 is also bent. Become. As described above, when the protective cover 40 is bent, it is desirable that the protective cover 40 bend in a certain direction in order to avoid being forced against the hose 17b. For this purpose, as shown in FIG. 15, the wire fastener 142 for making the protective cover 40 cylindrical is not provided in the axial direction of the protective cover 40, but is bent in the rotational direction by a predetermined angle. Installing. Accordingly, when the protective cover 40 is bent, the directionality is given, and the protective cover 40 is smoothly pressed without being pressed against the hose 17b provided therein.

  Further, as in the protective cover 50 shown in FIG. 16, spacers 52 made of foamed resin can be fixedly disposed on the inner surface of the cover main body 51. Thereby, a substantially constant annular gap 53 can be secured in the circumferential direction between the inner surface of the protective cover 50 and the outer surface of the hose 17b. As a result, the annular gap 53 functions as a heat insulating portion between the hose 17b and the outside air, and it is possible to suppress the hose 17b from being extremely heated or extremely cooled by the outside air temperature. it can. As a result, the flexibility and toughness of the hose 17b can be prevented or suppressed.

DESCRIPTION OF SYMBOLS 10 Work implement 11 Boom 12 Arm 13 Bucket 12a Arm cylinder 17 Hydraulic piping 17a Pipe 17b Hose 18 Connection part 19 Base 20 Screw part 21 Nut 22 Hose connection part 23 Nut 30, 40, 50 Protective cover 31, 41, 51 Cover body 31a 1st cover sheet 31b 2nd cover sheet 32, 34 surface fastener 33 attachment part 35 oil absorption mat 36 oil receiving pocket 37 bellows part 38 annular flexible sheet 42, 142 wire tape 43 covering tape 44 opening 45 possible Flexible sheet 46 Seal member 52 Spacer

Claims (6)

Constructs hydraulic piping and is installed so as to be bridged between mutually movable parts. Both ends serve as caps that are detachably connected to the connection ports of metal pipes or hydraulic equipment, and are attached to flexible hoses. A protective cover,
A cover body made of a flexible sheet member and mounted to cover the outer periphery of the hose;
Provided on both sides of the cover main body, in a state in which the hose is housed inside, is cylindrical, and is detachably fixed to the caps at both ends of the hose or the connecting port connecting these caps A protective cover for hydraulic piping, characterized in that it is composed of a part connecting part. The said side part connection part was comprised from the hook-and-loop fastener or the line fastener, The protective cover of the hydraulic piping of Claim 1 characterized by the above-mentioned. The cover body includes an oil leakage detector that covers the hose and expands due to an increase in internal pressure, and includes an oil leakage detector that makes the expansion state visible from the outside. The protective cover for hydraulic piping according to claim 1 or 2. The protective cover for hydraulic piping according to any one of claims 1 to 3, wherein an oil reservoir that can be expanded and contracted is formed in the cover body. The protective cover for hydraulic piping according to any one of claims 1 to 4, wherein the side connecting portion is inclined linearly or curvedly. When the cover body is cylindrical, a spacer member is provided to form a gap between the inner surface of the cover body and the outer surface of the hose. Item 6. A protective cover for hydraulic piping according to any one of Items 5 to 6.

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