JP4544171B2 - Cabin lifting device - Google Patents

Description

  The present invention relates to a cabin elevating device that elevates and lowers a cabin according to a work situation or the like in a working machine such as a hydraulic excavator, a crusher, or a crane.

  Conventionally, the work machine includes an upper body mounted on a self-propelled traveling body, a cabin provided on the upper body, and a cabin lifting device that lifts and lowers the cabin relative to the upper body. Things are known.

  The cabin elevating device includes a parallel link mechanism provided between the upper body and the cabin, and is configured to elevate the cabin by rotating the parallel link mechanism (for example, Patent Document 1).

  In this type of cabin elevating device, it is preferable to perform equipment maintenance at a position where the cabin is lowered most for safety. However, when there is a cabin at this position, equipment (for example, hydraulic piping) that is subject to maintenance may be disposed at a position where the cabin is obstructed and hidden. When performing maintenance, it is necessary to lift the cabin to a predetermined height position and hold it at this position.

  At that time, in order to ensure high work safety, it is desirable to mechanically lock the cabin at the position using a member such as a stopper.

Specifically, conventionally, after raising the cabin to a predetermined height position, a stopper or the like is interposed between the pair of links of the parallel link mechanism, and the stopper and each link are fixed with pins or the like. By doing so, the lift position of the cabin has been mechanically held by restricting the relative movement of the links.
JP 2003-184127 A

  However, when the cabin height position is held by the conventional method, it is necessary to separately perform the work of raising the cabin to a predetermined height position and the work of fixing the stopper or the like to each link. It was bad.

  In particular, in the conventional method, it is necessary to fix a stopper between the links at the height position while checking whether the cabin has been raised to a predetermined height position. In order to execute it efficiently, another operator was required in addition to the operator who performs the raising and lowering operation of the cabin.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a cabin elevating device capable of improving workability for mechanically holding the height position of the cabin.

In order to solve the above problem, the present invention is a cabin lifting device provided in a work machine having an upper body mounted on a self-propelled traveling body and a cabin provided in the upper body, A parallel link mechanism including a pair of upper and lower links for connecting the upper body and the cabin so that the cabin can be moved up and down between a preset upper limit position and a lower limit position, and one of the links A first engaging portion provided on the other link of the links, and a second engaging portion engageable with the first engaging portion, wherein the cabin has the upper limit position. The first engagement portion and the second engagement portion are moved by the first engagement portion to the engagement position with respect to the second engagement portion in response to the movement to the specific height position between the lower limit position and the second engagement portion. Each of the phosphors with the engagement portion facing the cabin descending direction. The first engagement portion engages with the second engagement portion in response to the movement of the cabin to the specific height position. The parallel link mechanism is configured so that both ends of each link are connected to the upper body and the cabin. The first engaging portion can be tilted about a tilting axis parallel to the rotating shaft with respect to the upper link of the links. The engagement lever is supported, and the engagement lever is moved by its own weight relative to the upper link by its own weight in accordance with the movement of the cabin to the specific height position. Towards the engagement position and at the specific height Is set at a height position where the distance between the links is the widest or a position lower than the height position, and the engagement lever is located in the longitudinal direction of each link at the specific height position. Engaging with the second engagement portion in a posture having a predetermined inclination angle around the tilt axis with respect to a direction perpendicular to the direction, and the second engagement portion regulates a change in the inclination angle. A cabin lifting device is provided.

  According to the present invention, since the first engagement portion and the second engagement portion provided in each link are engaged with each other, the relative movement of each link can be restricted. Can prevent movement.

  That is, when each link rotates, each link moves (slides) in the longitudinal direction while maintaining a parallel state. In the present invention, this relative movement is performed between the first engagement portion and the first engagement portion. Since it can regulate by engagement with 2 engaging parts, it can prevent mechanically that each link rotates, ie, a descent | fall of a cabin.

In the present invention, such a regulation can be performed in accordance with the movement of the cabin to a specific height position. Therefore, the operation for moving the cabin and the work for regulating the relative movement of both links are performed. Unlike the conventional method in which the control is performed separately, the regulation work and the cabin moving operation can be performed at the same time, and the workability can be improved.

  Therefore, in the present invention, the regulation work can be easily performed even by one operator who raises and lowers the cabin.

  Therefore, according to the present invention, it is possible to improve workability for mechanically holding the cabin height position.

  Furthermore, according to the present invention, an engageable state in which the links are engaged according to the movement of the cabin to the specific position, and an unengageable state in which the engagement is not performed regardless of the movement of the cabin. Therefore, it is possible to hold the cabin height position as necessary while allowing the cabin to freely move up and down during normal times.

Specifically, in the present invention, the parallel link mechanism, with both ends of each link is provided with a rotation shaft for each pivotably supported on the upper body and the cabin, the first engagement portion comprising the said engagement lever, which is tiltably supported on the tilt axis parallel to the pivot axis with respect to the upper link of each link, the engagement lever, the cabin to said specific height position in accordance with the movement, that is configured to be directed to the engagement position by relative movement with respect to the upper link by its free end to its own weight.

Thus, according to the present invention , since the engaging lever is configured to tilt with its own weight with respect to the upper link, the special lever can be moved to the specific position without requiring special power for moving the engaging lever. The engagement lever can be automatically moved to the engagement position in accordance with the movement of the cabin.

In the present invention, the specific height position is set to a height position where the distance between the two links is the widest or a position lower than the height position, and the engagement lever is set to the specific height. in the position, engaged with the second engaging portion in a posture having a predetermined inclination angle to the tilting axis with respect to a direction perpendicular to the respective longitudinal direction of each link, the second engaging portion, It is configured to regulate the change in the tilt angle.

Therefore, according to the present invention , it is possible to prevent the rotation of each link by causing the engagement lever to act like a tension rod between the two links.

  In other words, in order to lower the cabin at the cabin height position where the vertical interval of each link is the widest or at a position lower than this height position, the interval between the links needs to be narrowed. By restricting the change in the inclination angle of the engaging lever that is engaged with the second engaging portion, the engaging lever can be made to act like a tension rod between the two links. It is possible to regulate the rotation of each link while maintaining the interval.

  More specifically, an engagement shaft extending in parallel with the tilt shaft is formed at the free end of the engagement lever, and the second engagement portion is provided around the tilt shaft when the cabin is lowered. The engagement shaft that moves in the direction of opening is opened in a direction in which the engagement shaft can be received, and a fitting groove surrounded by a side wall with which the side surface of the received engagement shaft abuts can be formed.

  According to this configuration, when the cabin descends, the engaging shaft that moves relative to the upper link can be guided into the fitting groove, and the engaging lever and the second engaging portion can be engaged.

  The cabin lifting device further includes a connecting member that detachably connects the free end of the engaging lever and the upper link, and the engaging lever is connected to the free end and the upper link by the connecting member. And the engagement position where the cabin is engaged with the second engagement portion in response to the movement of the cabin to the specific height position, and the engagement position regardless of the position of the cabin. It is preferable to be configured to be able to switch between an engagement disabling state that keeps the state away from the disengaged state.

  According to this configuration, the engaging state in which the engaging lever and the second engaging portion are engaged with each other by a simple method of attaching and detaching the free end of the engaging lever and the upper link by the connecting member; Since it is possible to switch to the non-engageable state in which the engagement is not performed, the cabin height position can be maintained as necessary while allowing the cabin to freely move up and down during normal times.

  According to the present invention, workability for mechanically holding the cabin height position can be improved.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a side view schematically showing a cabin elevating device according to a preferred embodiment of the present invention, showing a state where the cabin is located between an upper limit position and a lower limit position. FIG. 2 is a side sectional view showing a part of the state where the cabin of FIG.

  Referring to the drawings, a cabin lifting / lowering device 1 is provided on an upper body 2 mounted on a self-propelled traveling body (for example, a crawler traveling body: not shown) of a work machine such as a hydraulic excavator. The cabin 3 is raised and lowered with respect to the upper body 2. In addition, it demonstrates below using the direction seen from the operator H in the cabin 3. FIG.

  Specifically, the lifting device 1 includes a parallel link mechanism 5 including an upper link (upper link) 5a and a lower link 5b provided between the bracket 4 standing on the upper body 2 and the cabin 3. A restricting means 6 for restricting the rotation of the links 5a and 5b by restricting the relative movement of the links 5a and 5b, and a hydraulic cylinder 7 for rotating the upper link 5a with respect to the bracket 4 are provided. .

  The parallel link mechanism 5 includes the upper link 5a and the lower link 5b, the rotation shaft 8 and the rotation shaft 9 that pivotally support the rear end portions of the links 5a and 5b on the bracket 4, respectively, and the links. A rotation shaft 10 and a rotation shaft 11 are provided to pivotally support the front end portion of 5a to the cabin 3 respectively.

  The rotating shafts 8 and 9 are arranged vertically above the bracket 4, the rotating shaft 8 is the rear end of the upper link 5a, and the rotating shaft 9 is the rear end of the lower link 5b. It is supported rotatably.

  On the other hand, the rotation shafts 10 and 11 are arranged vertically on a cabin bracket 3a formed at the rear portion of the cabin 3, the rotation shaft 10 is a front end portion of the upper link 5a, and the rotation shaft 11 is a lower link. The front end portions of 5b are rotatably supported.

  Therefore, the cabin 3 has a range from the lower limit position shown in FIG. 2 to the upper limit position (not shown) via the intermediate position shown in FIG. 1 while maintaining the posture by rotating both links 5a and 5b. It is possible to move up and down.

  The restricting means 6 includes an engaging part (first engaging part) 12 provided in the middle part of the upper link 5a and a slide block (second engaging part) 14 provided in the middle part of the lower link 5b. I have.

  3 is an enlarged view of the regulating means of FIG. 2, (a) is a side view, and (b) is a sectional view taken along line IIIb-IIIb of (a).

  Referring to FIG. 3, the engaging portion 12 includes a tilt shaft 15, a lock lever (engagement lever) 16 supported by the tilt shaft 15 so as to be rotatable with respect to the upper link 5 a, and the lock lever 16. A lock pin (engagement shaft and connecting member) 17 for fixing the free end to the upper link 5a is provided.

  The tilt shaft 15 is provided through the bracket 18a projecting downward from the upper link 5a and the base end of the lock lever 16 to the left and right. Further, the tilt shaft 15 is prevented from coming off from the bracket 18a and the lock lever 16 in the left-right direction.

  The lock lever 16 has a bifurcated shape in which the base end portion is divided into left and right, and the branch piece 16a and the branch piece 16b are arranged so as to sandwich the bracket 18a on the left and right, respectively. Since both the branch pieces 16a and 16b are penetrated together with the bracket 18a by the tilt shaft 15, the lock lever 16 can be tilted around the tilt shaft 15 with respect to the upper link 5a.

  Further, the lock lever 16 has a bifurcated shape whose free end is also divided into right and left, and an interval at which the branch piece 16c and the branch piece 16d can sandwich the bracket 18b provided behind the bracket 18a from side to side. They are formed apart by W1. This interval W1 is set slightly larger than the width dimension W2 of the slide block 14 described later.

  The lock pin 17 passes through the bracket 18b and the branch pieces 16c and 16d in the left-right direction, thereby fixing the free end of the lock lever 16 to the upper link 5a.

  Further, a retaining pin 17a orthogonal to the axial direction of the locking pin 17 can be inserted / removed, and when the retaining pin 17a is inserted, the retaining member 17c is prevented from slipping left and right from the branch pieces 16c, 16d. The retaining pins 17a can be extracted from the branch pieces 16c and 16d in a state where the retaining pins 17a are extracted.

  The slide block 14 is erected on the lower link 5b. The slide block 14 is formed in a substantially concave shape in a side view in which a rear portion and a front portion are a protruding portion 19 and a protruding portion 20 that protrude in a direction orthogonal to the longitudinal direction of the lower link 5b.

  The projecting portion 19 has a guide surface 19a whose rear end surface rises forward, and an inner side surface (side wall of the fitting groove) 19b constituting a groove (fitting groove) whose front portion opens forward. Has been.

  On the other hand, the rear end surface of the protruding portion 20 is a guide surface 20a that descends rearward and smoothly continues to the inner surface 19b.

  In the lifting device 1 configured as described above, when the cabin 3 moves to the lower limit position shown in FIG. 2, the front of the bracket 4 is blocked by the cabin 3, and the device disposed in the bracket 4. Maintenance (for example, hydraulic piping connected to the hydraulic cylinder 7) cannot be performed.

  Therefore, when performing maintenance, it is necessary to raise the cabin 3 to a certain height and then mechanically hold this position.

  Hereinafter, the operation | movement at the time of hold | maintaining the height position of the cabin 3 mechanically is demonstrated with reference to FIGS.

  First, at the lower limit position shown in FIG. 2, the lock pin 17 is pulled out from the lock lever 16 after the retaining pin 17 a is pulled out. As a result, the lock lever 16 is suspended from the upper link 5a by its own weight.

  The extracted lock pin 17 is moved away from the bracket 18 b by rotating the lock lever 16, and then inserted again into the branch pieces 16 a and 16 b of the lock lever 16, and the retaining pin 17 a is inserted into the lock pin 17. insert. As a result, the lock pin 17 is attached to the free end of the lock lever 16 which can be rotated in a state of being prevented from coming off.

  Next, as shown in FIG. 4A, when the cabin 3 is raised, the distance between the links 5a and 5b is widened, and the lower link 5b moves in a direction to retract backward relative to the upper link 5a. Therefore, the free end of the lock lever 16 moves to the front end side of the lower link 5b while sliding on the lower link 5b.

  In the process of moving the free end, the slide block 14 enters between the branch pieces 16c and 16d of the lock lever 16, and the abdomen of the lock pin 17 and the guide surface 19a exposed between the branch pieces 16c and 16d. The free end (lock pin 17) of the lock lever 16 gets over the protrusion 19 as shown in FIG. 4B along the guide surface 19a.

  In the present embodiment, the lock lever 16 is in a state in which the lock lever 16 is tilted rearward around the tilt shaft 15 from the direction D1 perpendicular to the longitudinal direction of the links 5a and 5b in a state where the protrusion 19 is overcome. The length dimension of the lever 16 and the arrangement position of the slide block 14 with respect to the lower link 5b are set.

  In this embodiment, the elevating position where the distance between the links 5a and 5b is the largest, that is, the direction D3 orthogonal to the direction D2 connecting the rotation shaft 8 and the rotation shaft 9 and the longitudinal direction thereof are parallel. The lock pin 17 gets over the protruding portion 19 at a rotation position below the rotation position of each link 5a, 5b.

  Then, when the cabin 3 is lowered from the state of FIG. 4B, the lower link 5b moves forward with respect to the upper link 5a while the distance between the two links 5a and 5b is narrowed. As a result of the pin 17 moving to the rear end side of the lower link 5b along the guide surface 20a, as shown in FIG. 5A, the pin 17 comes into contact with the inner surface 19b of the groove of the slide block 14, and the lock lever Sixteen free ends engage the slide block 14.

  That is, in the state of FIG. 5A, the free end of the lock lever 16 is further moved to the rear end side of the lower link 5b in order to rotate both the links 5a and 5b in the direction in which the cabin 3 descends. In other words, it is necessary to tilt the lock lever 16 backward. However, since the side surface of the lock pin 17 is in contact with the inner side surface 19b of the slide block 14, the lock pin 17 is between the links 5a and 5b. As a result of acting like a tension rod, the lowering of the cabin 3 is mechanically restricted at this position.

  In this embodiment, in this engageable state, the lock lever 16 maintains a posture inclined backward with an inclination angle θ1 about the tilting axis 15 from the direction D4 perpendicular to the longitudinal direction of the links 5a, 5b. The length dimension of the lock lever 16 and the arrangement position of the slide block 14 with respect to the lower link 5b are set.

  Then, as shown in FIG. 5 (b), the cabin 3 is once raised and the free end of the lock lever 16 is rotated in a state where the lock pin 17 is detached from the groove of the slide block 14, By fixing the free end to the upper link 5a by the lock pin 17, the engageable state can be released.

  As described above, according to the lifting device 1, the lock lever 16 and the slide block 14 provided on the links 5a and 5b are engaged with each other, thereby restricting the relative movement of the links 5a and 5b. Therefore, the rotation of the links 5a and 5b can be prevented.

  That is, when the links 5a and 5b rotate, the links 5a and 5b move (slide) back and forth while maintaining a parallel state. In the lifting device 1, the relative movement is performed. Since it can restrict | limit by engagement with the lock lever 16 and the slide block 14, rotation of each link 5a, 5b, ie, the descent | fall of the cabin 3, can be prevented mechanically.

  And in the said raising / lowering apparatus 1, since such a regulation can be performed according to moving to the specific height position of the cabin 3, the operation | movement which moves the cabin 3, and the relative movement of both links 5a and 5b Can be performed simultaneously with the work for restricting the above, and workability can be improved.

  Therefore, in the lifting / lowering apparatus 1, the operation of maintaining the height position of the cabin 3 can be easily performed even by one operator who lifts / lowers the cabin 3.

  Therefore, according to the lifting / lowering device 1, workability for mechanically holding the height position of the cabin 3 can be improved.

  Moreover, according to the raising / lowering apparatus 1, the state which engages each link 5a, 5b by the simple method of attaching / detaching the free end of the lock lever 16 and the upper link 5a with the lock pin 17 (engageable state). Since it is possible to switch between a state in which engagement is not performed (a state in which engagement is not possible), the cabin 3 can be freely moved up and down during normal times, and the height position of the cabin can be maintained as necessary. Can do.

  According to the lifting device 1 in which the lock lever 16 is tilted by its own weight around the tilt shaft 15 with respect to the upper link 5a, the lock lever 16 is locked according to the movement of the cabin 3 without requiring any special power to move the lock lever 16. The lever 16 can be automatically moved to the slide block 14 side.

  Further, in the lifting / lowering device 1, since the change of the inclination angle θ1 (see FIG. 5A) of the lock lever 16 engaged with the slide block 14 is restricted, the lock lever 16 is connected to both links 5a. The link 5a, 5b can be prevented from rotating by acting like a tension rod between 5b.

  That is, in the above embodiment, the lock lever 16 and the slide block 14 are engaged in the lifting range below the position of the cabin 3 where the vertical distance between the links 5a, 5b is the widest. In order to lower the cabin 3, the interval between the links 5a and 5b needs to be narrowed, but by restricting the change in the inclination angle θ1 of the lock lever 16 engaged with the slide block 14, Since the lock lever 16 can act like a tension rod between the two links 5a and 5b, the rotation of each link can be restricted while maintaining the distance between the links 5a and 5b.

  Hereinafter, a lifting apparatus according to another embodiment of the present invention will be described with reference to FIG. In addition, the same code | symbol is attached | subjected about the structure similar to the said embodiment, the description is abbreviate | omitted, and the structure different from the said embodiment is mainly demonstrated.

  The elevating device 21 includes a regulating means 24 including an engaging portion (first engaging portion) 22 and a slide block (second engaging portion) 23.

  The engaging portion 22 is supported by the tilt lever 15 so that the lock lever 16 is pivotable with respect to the rear bracket 18b, and the free end of the lock lever 16 is supported by the lock pin 17 on the front bracket 18a. It is different from the above embodiment in that it can be attached and detached.

  The slide block 23 has a configuration corresponding to the protruding portion 19 (see FIG. 3A) in the above embodiment. That is, the slide block 23 is a guide surface 23a whose rear end face is raised forward, and its front part is an inner side face 23b constituting a groove opening forward.

  The engaging portion 22 and the slide block 23 are different in the relative positional relationship from the above embodiment in order to enable the operation described later.

  Hereinafter, the operation when the height position of the cabin 3 is mechanically held in the lifting device 21 will be described with reference to FIGS.

  First, at the lower limit position shown in FIG. 6, the lock pin 17 is pulled out from the lock lever 16 after the retaining pin 17 a is pulled out. Thereby, as shown to (a) of FIG. 7, the free end (lock pin 17) of the lock lever 16 is mounted on the guide surface 23a of the slide block 23 with the dead weight.

  Next, when the cabin 3 is raised, the distance between the links 5a and 5b is widened, and the lower link 5b moves backward with respect to the upper link 5a. Therefore, the free end of the lock lever 16 is It is guided forward along the guide surface 23a of the slide block 23, and finally gets over the slide block 23 as shown in FIG.

  In the present embodiment, when the slide block 23 is passed over, the lock pin 17 is introduced into the groove of the slide block 23 by its own weight and abuts against the inner side surface 23b. In this state, the lock lever 16 The length dimension of the lock lever 16 and the arrangement position of the slide block 23 with respect to the lower link 5b are set so as to maintain the posture inclined forward about the tilting axis 15.

  Then, when the cabin 3 is lowered from the state shown in FIG. 7B, the lower link 5b moves forward with respect to the upper link 5a while the distance between the links 5a and 5b is narrowed. As shown in FIG. 8A, the lock pin 17 contacts the inner surface 23 b of the groove of the slide block 23, and the free end of the lock lever 16 is engaged with the slide block 23.

  That is, in the state of FIG. 8A, in order to rotate both the links 5a and 5b in the direction in which the cabin 3 descends, the lower link 5b needs to move forward with respect to the upper link 5a. Since the side surface of the lock pin 17 is engaged with the inner side surface 23b of the slide block 23, the links 5a and 5b are relatively moved by the lock lever 16 spanned between the inner side surface 23b and the lock pin 17. As a result, the lowering of the cabin 3 is mechanically restricted at this position.

  In the present embodiment, in this engageable state, the lock lever 16 maintains a posture inclined forward with an inclination angle θ2 around the tilt axis 15 from the direction D5 perpendicular to the longitudinal direction of each link 5a, 5b. The length dimension of the lock lever 16 and the arrangement position of the slide block 23 with respect to the lower link 5b are set.

  Then, as shown in FIG. 8B, in a state where the cabin 3 is once raised and the lock pin 17 is detached from the groove of the slide block 23, the free end of the lock lever 16 is rotated to move to the upper link 5a. By fixing, the engageable state can be released.

  In each of the above embodiments, the configuration in which the base end portion of the lock lever 16 is pivotally supported by the upper link 5a is described. However, the base end portion of the lock lever 16 is rotated to the lower link 5b. It can also be attached as possible.

  For example, a slit (second engaging portion) that penetrates the upper link 5a in the left-right direction is provided, and a slide shaft that is slidably inserted into the slit is formed at the free end of the lock lever 16, and the lock lever 16, the two links 5a and 5b can be connected.

  In this case, the sliding shaft slides with respect to the upper link 5a along a predetermined trajectory defined by the slit, thereby allowing free rotation of both the links 5a and 5b. When the groove 5b is rotated to a predetermined height position, a groove portion into which the sliding shaft is dropped is formed so as to be extended from the slit, so that the rotation of both links 5a and 5b is restricted at this rotational position. The

  Further, in this case, by separately providing a member that closes the groove portion, the engagement between the sliding shaft and the groove portion can be prevented to make the engagement impossible state.

It is a side view which shows roughly the cabin raising / lowering device which concerns on preferable embodiment of this invention, and has shown the state which has a cabin in the position between an upper limit position and a minimum position. It is side surface sectional drawing which abbreviate | omits and shows a part of the state by which the cabin of FIG. 1 was made into the minimum position. FIG. 3 is an enlarged view of the regulating means in FIG. 2, (a) is a side view, and (b) is a sectional view taken along line IIIb-IIIb in (a). It is side surface sectional drawing which shows operation | movement of the raising / lowering apparatus of FIG. 1, (a) has shown the state which started the raise of a cabin, (b) has each shown the state in which the lock pin got over the protrusion part. It is side surface sectional drawing which shows operation | movement of the raising / lowering apparatus of FIG. 1, (a) has shown the state which the lock pin and the slide block engaged, (b) has each shown the state which cancels | releases engagement. It is side surface sectional drawing which shows the raising / lowering apparatus of the cabin which concerns on another embodiment of this invention. It is side surface sectional drawing which shows operation | movement of the raising / lowering apparatus of FIG. 6, (a) has shown the state which started the raise of a cabin, (b) has each shown the state in which the lock pin got over the slide block. It is side surface sectional drawing which shows operation | movement of the raising / lowering apparatus of FIG. 6, (a) has shown the state which the lock pin and the slide block engaged, (b) has each shown the state which cancels | releases engagement.

DESCRIPTION OF SYMBOLS 1 Lifting apparatus 2 Upper body 3 Cabin 5 Parallel link mechanism 5a Upper link (upper link)
5b Lower link 6 Restricting means 8-11 Rotating shaft 12 Engaging portion (first engaging portion)
14 Slide block (second engaging part)
16 Lock lever (engagement lever)
19b inner surface (side wall of fitting groove)
21 Lifting device 22 Engaging portion (first engaging portion)
23 Slide block (second engaging part)
23b inner surface (side wall of fitting groove)
D1 Direction perpendicular to the longitudinal direction of the link D3 Longitudinal direction of each link when the interval is widest θ1, θ2 Inclination angle

Claims (3)

A cabin lifting device provided in a work machine having an upper body mounted on a self-propelled traveling body and a cabin provided in the upper body,
A parallel link mechanism including a pair of upper and lower links connecting the upper body and the cabin so that the cabin can be moved up and down between a preset upper limit position and a lower limit position;
A first engagement portion provided on one of the links;
A second engagement portion provided on the other link of the links, and engageable with the first engagement portion;
When the cabin moves to a specific height position between the upper limit position and the lower limit position, the first engagement portion moves to the engagement position with respect to the second engagement portion. The first engaging portion and the second engaging portion engage with each other so as to regulate relative movement of the links in the cabin descending direction;
The first engagement portion includes an engageable state in which the cabin is engaged with the second engagement portion in accordance with the movement of the cabin to the specific height position, and the engagement position regardless of the position of the cabin. switchably configured between an engaged impossible state to keep away state from
The parallel link mechanism includes a rotation shaft that pivotally supports both ends of each link on the upper body and the cabin, respectively, and the first engagement portion is located on the upper side of the links. An engagement lever supported so as to be tiltable about a tilting axis parallel to the rotation axis with respect to the link, and the engagement lever has a free end corresponding to the movement of the cabin to the specific height position. Is moved relative to the upper link by its own weight, toward the engagement position,
The specific height position is set to a height position where the distance between the links is the widest or a position lower than the height position, and the engagement lever is connected to each link at the specific height position. The second engagement portion engages with the second engagement portion in a posture having a predetermined inclination angle around the tilt axis with respect to a direction perpendicular to each of the longitudinal directions, and the second engagement portion changes the inclination angle. Cabin lifting device characterized by regulating . An engagement shaft extending in parallel with the tilt shaft is formed at a free end of the engagement lever, and the second engagement portion moves about the tilt shaft when the cabin descends. 2. The cabin according to claim 1, wherein a fitting groove is formed that opens in a direction in which the axial shaft can be received and is surrounded by a side wall against which a side surface of the received engaging shaft abuts. lift device. It further includes a connecting member that removably connects the free end of the engaging lever and the upper link, and the engaging lever is attached and detached by the connecting member. An engagement state in which the cabin is engaged with the second engagement portion in response to the movement to the specific height position, and an engagement in which the cabin is kept away from the engagement position regardless of the position of the cabin. The cabin lifting / lowering device according to claim 1 or 2, wherein the cabin lifting / lowering device is switchable between an impossible state and a disabled state.

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