JP2014105455A - Cab head guard device for construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cab head guard device for a construction machine that can suppress a displacement amount of a guard when the guard is loaded by a falling body etc.SOLUTION: A hinge member 15 which connects a front guard (movable guard member) 13 to a cab side is provided at a front end part of the front guard 13 which protects a roof of a cab 4. A lock mechanism 16 which connects the front guard 13 to the cab side is provided at an opposite-side end of the hinge member 15. Consequently, the front guard 13 is fitted to the cab 4 to be opened and closed between a closing state in which a roof upper surface is covered and an opening state in which the roof upper surface is opened. A load transmission member 20 which transmits a load to the cab 4 when the load is placed on the front guard 13 from above is provided between the hinge member 15 and the lock mechanism 16.

Description

  The present invention relates to a cab head guard device for protecting a cab roof from a fallen object or the like in a construction machine such as a hydraulic excavator.

  In a conventional cab head guard device for a construction machine, a roof of a cab is provided with a skylight, and a headguard device for protecting the roof including the skylight from falling objects is known above the roof. This head guard device is composed of a front guard and a rear guard. The rear guard is fixed, whereas the front guard is openable so that it can be opened when cleaning the skylight. . Specifically, the front guard is formed in a lattice shape as a whole, and is pivotally attached to the cab by a hinge mechanism at the front end, and a mounting portion provided at the rear end is bolted to the front end of the rear guard. (For example, refer to Patent Document 1).

JP 2008-163595 A

  On the other hand, as a head guard device of the same type, there is one configured such that an attachment portion provided at a rear end portion of a front guard is locked by a lock mechanism provided at a front end portion of the rear guard. In this head guard device, a stopper that positions the height of the front guard by contacting the mounting portion when the front guard is closed is provided at a position adjacent to the locking mechanism at the front end of the rear guard. That is, the stopper is provided at substantially the same position as the lock mechanism. This arrangement is conceptually shown in FIG. In FIGS. 9A and 9B, 113 is a front guard and 112 is a rear guard.

  However, as shown in FIG. 9B, when the front guard 113 is enlarged and the mounting pitch (interval) between the front end hinge mechanism and the rear end lock mechanism is increased, the strength of the front guard 113 is increased. It becomes difficult to secure. That is, when a load such as a fallen object is received at the front-rear direction intermediate position of the front guard 113, the displacement amount D2 becomes larger than the displacement amount D1 in FIG. 9A, and it is difficult to protect the operator. Become.

  Accordingly, an object of the present invention is to provide a cab head guard device for a construction machine that can suppress the amount of displacement of the guard when a load is applied to the guard due to a fallen object or the like.

  In order to achieve the above object, according to the present invention, first connecting means for connecting the movable guard member to the cab side is provided at any of the front, rear, left and right ends of the movable guard member that protects the roof of the cab. The second connecting means for connecting the movable guard member to the cab side is provided at the end opposite to the first connecting means so that the movable guard member covers the roof upper surface and the roof upper surface. A load transmitting member configured to be attached to the cab so as to be openable and closable between an open state and an open state, and transmitting the load to the cab when the movable guard member receives a load from above, the first connection And a cab head guard device for a construction machine provided between the first connecting means and the second connecting means.

  Here, the first connecting means and the second connecting means are provided at a front end portion and a rear end portion of the movable guard member, respectively, and the load transmission member is a seating space for an operator in the front-rear direction of the cab. Or it is preferable to be located ahead of it.

  Furthermore, it is preferable that the load transmission member is provided in at least two locations corresponding to the left and right beams of the cab.

  Further, the load transmission member is attached to a frame other than the frame provided with the first connection means and the second connection means among the front, rear, left and right frames constituting the outer frame of the movable guard member, The frame to which the load transmitting member is attached preferably has a closed cross section only in a region where the load transmitting member is attached, and has an open cross section in other regions.

  The first connecting means is a hinge member provided at a front end portion or a rear end portion of the movable guard member, and the second connecting means is provided at an end portion opposite to the hinge member, It is preferable that the holding means holds the movable guard member in a closed state.

  In addition, it is preferable that the load transmission member is in contact with the cab with the movable guard member closed.

  Furthermore, the load transmission member includes an attachment portion that is attached to the movable guard member and a contact portion that contacts the cab, and the attachment portion is configured to be able to adjust a height protruding from the movable guard member. Therefore, it is preferable that the load transmission member functions as a stopper for positioning the height of the movable guard member with respect to the cab.

  Furthermore, the contact portion is preferably made of a material that absorbs vibration.

  According to the cab head guard device for a construction machine according to claim 1, when the movable guard member receives a load from above, the load transmitting member for transmitting the load to the cab includes the first connecting means and the second connecting means. It is provided between. For this reason, when the movable guard member receives a load due to a fallen object or the like, the load is transmitted to the cab via the load transmission member. As a result, the displacement of the movable guard member can be suppressed. This is particularly effective when the mounting pitch (interval) of the enlarged movable guard member is increased and it is difficult to ensure the strength of the movable guard member itself. With this configuration, it is not necessary to add an attachment point (support point) for the movable guard member.

  According to the cab head guard device for a construction machine according to claim 2, the first connecting means and the second connecting means are provided at the front end portion and the rear end portion of the movable guard member, respectively, and the load transmitting member is the cab head guard. With respect to the front-rear direction, it is located in front of the operator's seating space. According to this configuration, the operator can be efficiently protected by arranging the load transmission member at a position close to the operator.

  According to the cab head guard device for a construction machine according to claim 3, the load transmission members are provided at at least two locations corresponding to the left and right beams of the cab. With this configuration, the load applied to the movable guard member is transmitted to the left and right beams of the cab via the load transmission member. Since the cab beam is relatively strong, it can be reliably loaded.

  According to the cab head guard device for a construction machine according to claim 4, the load transmitting member is a frame provided with the first connecting means and the second connecting means among the front, rear, left and right frames constituting the outer frame of the movable guard member. The frame to which the load transmission member is attached has a closed cross section only in a region where the load transmission member is attached, and has an open cross section in other regions. For this reason, compared with the structure which makes the whole area | region of a flame | frame the closed cross section, it can be set as the structure which suppressed the cost as a whole, ensuring the intensity | strength in the load transmission member vicinity.

  According to the cab head guard device for a construction machine according to claim 5, the first connecting means is a hinge member provided at a front end portion or a rear end portion of the movable guard member, and the second connecting means is a hinge member. It is a holding means that is provided at the opposite end and holds the movable guard member in a closed state. According to such a structure, the movable guard member can be easily opened and closed with a simple support structure.

  According to the cab head guard device for a construction machine according to the sixth aspect, the load transmission member is in contact with the cab with the movable guard member closed. Therefore, even if the holding means has a backlash, this can be absorbed.

  According to the cab head guard device for a construction machine according to claim 7, the load transmission member includes an attachment portion attached to the movable guard member and a contact portion contacting the cab, and the attachment portion protrudes from the movable guard member. The load transmission member functions as a stopper for positioning the height of the movable guard member with respect to the cab. Therefore, it is not necessary to provide a separate stopper, and the cost can be reduced.

  According to the cab head guard device for a construction machine according to claim 8, the contact portion is made of a material that absorbs vibration. For this reason, it is possible to absorb the vibration caused by the contact between the contact portion and the cab when the movable guard member is closed or during operation.

1 is a schematic side view showing an appearance of a hydraulic excavator equipped with a cab head guard device according to an embodiment of the present invention. The schematic perspective view which shows the cab of the hydraulic shovel which mounted | wore with the cab head guard apparatus by this embodiment. The perspective view which shows the cab head guard apparatus by this embodiment. The top view which shows the cab head guard apparatus by this embodiment. The side view which shows the cab head guard apparatus by this embodiment. The schematic side view of the cab for showing the positional relationship of a load transmission member and an operator's seating space. Sectional drawing which shows the cross section (closed cross section) of the side frame in the area | region where the load transmission member was attached (VII-VII sectional view taken on the line of FIG. 4). Sectional drawing which shows the general cross section (open cross section) of a side frame (VIII-VIII sectional view taken on the line of FIG. 4). In the conventional cab head guard apparatus, it is a conceptual diagram which shows the displacement of a guard when a load is added to a movable guard member by a fallen object, (b) is the situation where the movable guard member was enlarged compared with (a) Indicates.

  A cab head guard device for a construction machine according to an embodiment of the present invention will be described with reference to FIGS. In the present embodiment, a hydraulic excavator will be described as an example of a construction machine.

  As shown in FIG. 1, the hydraulic excavator 1 includes a crawler-type lower traveling body 2A, an upper revolving body 2B mounted on the lower traveling body 2A so as to be rotatable about a vertical axis, and a front of the upper revolving body 2B. And the work attachment 3 attached to the part. The upper swing body 2B is provided with a cab (operator's cab) 4, and each operation of turning, running, and attachment operation is performed in the cab 4.

  Further, the roof 4A of the cab 4 is provided with a skylight 5 (FIG. 2) for securing an upper field of view at the front part, and the cab head guard device 11 for protecting the roof 4A including the skylight 5 from falling objects. Is mounted on the roof 4A. A front guard 6 for protecting the front window is attached to the front surface of the cab 4.

  The cab head guard device 11 will be described. As shown in FIGS. 3 to 6, the cab head guard device 11 covers the rear part of the roof 4A of the cab 4 from above and protects it from falling objects, and covers the front part of the roof 4A from above. And a front guard 13 for protection.

  The rear guard 12 has a substantially flat plate shape and is fixed to the upper surface of the rear portion of the roof 4A with a bolt. The rear guard 12 is a fixed guard that is basically not removed even during cleaning or the like.

  The front guard 13 is formed in a lattice shape as a whole, and is formed in a letter shape in a side view in which the front portion is inclined downwardly so as to follow the curved surface of the front portion of the roof 4A. As shown in FIG. 4, the front guard 13 has an outer frame formed by a front frame 13F, a rear frame 13B, a right frame 13R, and a left frame 13L, and vertical and horizontal bars that form a lattice are disposed inside the front frame. The vertical and horizontal bars are angled so as not to obstruct the view from the driver as much as possible.

  As shown in FIG. 3, the front end portion (front frame 13 </ b> F) of the front guard 13 is attached to the cab 4 via a support member 14. Specifically, a long support member 14 extending in the left-right direction is fixed to the front corner portions 4C of the left and right beams 4L, 4R of the cab 4 with bolts. The front frame 13F of the front guard 13 is pivotally attached to the support member 14 by left and right hinge members 15 (an example of first connecting means). With this configuration, the front guard 13 rotates around the hinge member 15 as a fulcrum to cover the skylight 5 as shown in FIGS. As shown in FIG. 2, it can be opened and closed between an open posture (open state) at the time of cleaning which is inclined upward and opens the top of the skylight 5.

  As shown in FIGS. 4 and 5, left and right lock mechanisms 16 (an example of second connecting means) are provided at the rear end portion (rear frame 13 </ b> B) of the front guard 13. When the lock mechanism 16 engages with a striker 17 (FIG. 5) provided at the front end of the rear guard 12, the closed posture of the front guard 13 is maintained.

  The structure of the left and right frames 13R and 13L of the front guard 13 will be described. Since the left and right frames 13L and 13R basically have a symmetrical structure, the right frame 13R will be described with reference to FIGS.

  As shown in FIG. 7, the right frame 13 </ b> R has a closed cross section in a region R <b> 1 (FIG. 4) where the load transmission member 20 is attached. That is, in the region R1, the right frame 13R has a closed cross-section (a square shape) in which the second L-shaped member 13R2 provided only in the region R1 is joined to the first L-shaped member 13R1 extending over the entire length of the right frame 13R. ) Structure.

  Further, a mounting hole 13h for mounting the load transmission member 20 is formed in the right frame 13R (more specifically, the first L-shaped member 13R1 and the reinforcing member 13R3 provided therebelow) in the region R1. Yes. Two nuts 23 are fixed to the right frame 13R so as to sandwich the mounting hole 13h vertically.

  On the other hand, as shown in FIG. 8, the right frame 13R has an open cross section in a region R2 (FIG. 4) other than the region R1 to which the load transmission member 20 is attached. That is, in the region R2, the right frame 13R has an open cross-sectional (L-shaped) structure including only the first L-shaped member 13R1 extending over the entire length of the right frame 13R.

  Next, the load transmission member (stopper) 20 will be described. The load transmission member 20 is for transmitting the load to the cab 4 when the front guard 13 receives a load such as a fallen object from above, and at the same time, positions the height of the front guard 13 with respect to the cab 4. It also has a stopper function.

  As shown in FIGS. 4 and 5, one load transmission member 20 is attached to each of the right frame 13 </ b> R and the left frame 13 </ b> L of the front guard 13. As shown in FIG. 5, the left and right beams 4L and 4R of the cab 4 (only the beam 4L is shown in FIG. 5) and the left and right frames 13R and 13L of the front guard 13 (only the left frame 13L is shown in FIG. 5). Between them, a damper 24 for smoothly opening and closing the front guard 13 is attached, and the load transmission member 20 is provided at a position slightly rearward of the attachment portion 24A of the damper 24 in the left and right frames 13R and 13L. ing.

  As shown in FIG. 6, the load transmission member 20 is located between the hinge member 15 and the lock mechanism 16 in the front-rear direction and in front of the operator's seating space or more. More specifically, the load transmission member 20 is located slightly forward of the front-rear direction center line CL of the seat portion 25A of the operator's seat 25. By arranging the load transmission member 20 at a position close to the operator (particularly the head), the operator can be efficiently protected.

  5, the distance between the support position of the front guard 13 by the hinge member 15 and the support position of the lock mechanism 16 and the striker 17 is L1, and the support position of the front guard 13 by the load transmission member 20 and the lock mechanism. When the distance from the support position by 16 and the striker 17 is L2, in this embodiment, the ratio of L2 / L1 is about 15 to 20%. When the distance between the load transmission member 20 and the lock mechanism 16 is too small, the effect of the load transmission member 20 as an intermediate support point is reduced. On the other hand, in order to fulfill the function of the stopper described above, the load transmission member 20 is preferably located at a position close to the rear end portion of the front guard 13, that is, the lock mechanism 16. Therefore, in this embodiment, the front-rear direction position of the load transmission member 20 is set as described above.

  Moreover, the load transmission member 20 is provided in two places corresponding to the left and right beams 4L and 4R of the cab 4 in the left-right direction. The beams 4L and 4R have higher strength than the skylight 5 or the like. Therefore, when the load applied to the front guard 13 is transmitted to the beams 4L and 4R via the load transmission member 20, the load can be reliably received.

  The structure of the load transmission member 20 will be described in detail. As shown in FIG. 7, the load transmission member 20 includes the mounting portion 21 attached to the front guard 13 (more specifically, the right frame 13R and the left frame 13L), and the cab 4 ( Specifically, a contact portion 22 that contacts the left and right beams 4L, 4R) is provided. The mounting portion 21 is a metal part in which a round bar with a thread groove processed on the surface and a disc-shaped head portion are integrated, and the two nuts 23 are screwed together by the thread groove. Yes. The contact portion 22 is formed of a material that absorbs vibration, such as rubber, and is fixed to the head portion of the attachment portion 21. With such a configuration, the load transmitting member 20 moves in the vertical direction by gripping and rotating the contact portion 22, so that the height at which the load transmitting member 20 protrudes downward from the right frame 13 </ b> R can be adjusted. . Accordingly, the height of the front guard 13 in the closed state can be adjusted and functions as a stopper.

  According to the cab head guard device 11 according to the present embodiment, when the front guard 13 receives a load due to a fallen object or the like, this load is transmitted to the cab 4 via the load transmission member 20. As a result, the displacement of the front guard 13 can be suppressed. In addition, when subjected to a load, stress concentration around the rear end of the front guard 13 can be reduced. As described with reference to FIG. 9B, this is particularly effective when the mounting pitch (interval) is increased in the enlarged front guard 13 and it is difficult to ensure the strength of the front guard 13 itself. It is. With this configuration, it is not necessary to add an attachment point (support point) for the front guard 13.

  Moreover, in this embodiment, since the hinge member 15 and the lock mechanism 16 are used as the first and second connecting means, the opening / closing operation of the front guard 13 can be easily performed with a simple support structure.

  Further, the left and right frames 13L and 13R of the front guard 13 have a structure in which only the region R1 to which the load transmission member 20 is attached has a closed cross section, and the other region R2 has an open cross section. For this reason, compared with the structure which made the whole area | region of the right and left frame into the closed cross section, it can be set as the structure which suppressed the cost as a whole, ensuring the intensity | strength in the load transmission member 20 vicinity.

  Furthermore, since the load transmission member 20 also functions as a stopper as described above, there is no need to provide a separate stopper, and costs can be reduced. Further, since the contact portion 22 comes into contact with the cab 4 with the front guard 13 being closed, this can be absorbed even when the lock mechanism 16 has some backlash. Furthermore, since the contact portion 22 is formed of a material such as rubber, it is possible to suppress vibrations caused by the impact when the front guard 13 is closed and the contact between the contact portion 22 and the cab 4 during machine operation.

  Moreover, in this embodiment, the load transmission member 20 is provided in the front guard 13, and it is not necessary to newly provide a special structure in the cab 4 and the rear guard 12. FIG. Therefore, the above effect can be achieved at low cost.

<Modification>
The cab head guard device for a construction machine according to the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made within the scope described in the claims.

  For example, in the above-described embodiment, the load transmission member 20 is attached to the front guard 13, but may be attached to the cab 4 side (for example, the left and right beams 4L and 4R).

  In the embodiment described above, the hinge member 15 has a rear opening configuration provided at the front end portion of the front guard 13, but the configuration is not limited thereto. That is, the hinge member may have a front opening configuration provided at the rear end portion of the movable guard (front guard), or the hinge member may have a lateral opening configuration provided at the left or right end portion of the movable guard. .

  In the embodiment described above, the hinge member 15 and the lock mechanism 16 are used as the first connection means and the second connection means, but a slide mechanism may be used. In this case, for example, a guide rail can be provided on the left and right beams of the cab, and the movable guard can be slid back and forth along the guide rail to be openable.

  Further, as a means for maintaining the movable guard closed posture, a fastener such as a bolt may be used instead of the lock mechanism 16. Or you may use fasteners, such as a volt | bolt, in both the 1st and 2nd connection means.

  In the embodiment described above, the load transmission members 20 are provided at two locations corresponding to the left and right beams 4L and 4R of the cab, but the number of load transmission members is not particularly limited. That is, the load transmission member may be provided only at one place, or may be provided at three or more places.

  Further, the rear guard 12 (fixed guard) is not necessarily required.

  As described above, the cab head guard device for a construction machine according to the present invention is useful as a cab head guard device for protecting a cab and an operator of a construction machine such as a hydraulic excavator used for construction work from falling objects. It is.

1 hydraulic excavator, 2A lower traveling body, 2B upper turning body,
3 work attachment, 4 cab, 4A roof, 4C front corner,
4L, 4R Beam, 5 Skylight, 6 Front guard, 11 Cab head guard device, 12 Rear guard, 13 Front guard, 13B Rear frame, 13F Front frame, 13L Left frame, 13R Right frame, 13h Mounting hole, 14 Support member ,
15 hinge member, 16 lock mechanism, 17 striker, 20 load transmission member,
21 attachment part, 22 contact part, 23 nut, 24 damper, 24A attachment part, 25 seat, 25A seat part.

Claims (8)

A first connecting means for connecting the movable guard member to the cab side is provided at one of the front, rear, left and right ends of the movable guard member that protects the roof of the cab, and the end opposite to the first connecting means. Is provided with second connecting means for connecting the movable guard member to the cab side so that the movable guard member can be opened and closed between a closed state in which the roof upper surface is covered and an open state in which the roof upper surface is opened. Configured to be attached to
When the movable guard member receives a load from above, a load transmission member for transmitting the load to the cab is provided between the first connection means and the second connection means. Cab head guard device for construction machinery. The first connecting means and the second connecting means are provided at a front end portion and a rear end portion of the movable guard member, respectively.
2. The cab head guard device for a construction machine according to claim 1, wherein the load transmission member is positioned in front of or in front of an operator's seating space with respect to a cab longitudinal direction.   3. The cab head guard device for a construction machine according to claim 2, wherein the load transmission member is provided in at least two locations corresponding to left and right beams of the cab. The load transmitting member is attached to a frame other than the frame provided with the first connecting means and the second connecting means among the front, rear, left and right frames constituting the outer frame of the movable guard member,
The frame to which the load transmission member is attached has a closed cross section only in a region where the load transmission member is attached, and has an open cross section in other regions. A cab head guard device for a construction machine according to 1. The first connecting means is a hinge member provided at a front end portion or a rear end portion of the movable guard member,
The said 2nd connection means is a holding means which is provided in the edge part on the opposite side to the said hinge member, and hold | maintains the said movable guard member in a closed state, It is any one of Claim 1 to 4 characterized by the above-mentioned. The cab head guard device for the construction machine described.   The cab head guard device for a construction machine according to claim 5, wherein the load transmission member is in contact with the cab when the movable guard member is closed. The load transmission member includes an attachment portion attached to the movable guard member, and a contact portion that contacts the cab,
The mounting portion is configured to be capable of adjusting a height protruding from the movable guard member, and the load transmitting member functions as a stopper for positioning the height of the movable guard member with respect to the cab. The cab head guard device for a construction machine according to claim 6. The cab head guard device for a construction machine according to claim 7, wherein the contact portion is made of a material that absorbs vibration.

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