Truck-mounted crane

Abstract

The present invention provides a truck-mounted crane having a mechanical link mechanism that can tolerate dimensions outside the tolerance range when the accuracy of the support shaft, which serves as the rotation center of the link member, is outside the tolerance range. [Solution] The mechanical link mechanism 30 of the truck-mounted crane 10 converts the operation of the operating handle 25 into the operation of the spool 27 of the hydraulic valve 26. One of the multiple link members constituting the mechanical link mechanism 30 is composed of a first member 43 and a second member 44, and the length of the link member can be adjusted by changing the combined position of the first member 43 and the second member 44. With this configuration, even if the accuracy of the support shaft, which is the rotation center of the link member, is outside the tolerance range, the length of the link member can be adjusted to allow the dimension outside the tolerance range. Therefore, in the assembly of the mechanical link mechanism 30, it is not necessary to remanufacture the support shaft, and work efficiency is improved.

Description

Technical Field

[0001] The present invention relates to a loading truck crane. More specifically, the present invention relates to a loading truck crane capable of operating a jack mounted on an outrigger using a mechanical link mechanism.

Background Art

[0002] There are models of loading truck cranes equipped with a self-loader function. This self-loader function is a function in which a long jack provided on the chassis frame lifts the front side of the vehicle body and tilts the loading platform, and by this function, construction machinery or heavy machinery can be easily loaded onto the loading platform of the loading truck crane.

[0003] Patent Document 1 discloses a loading truck crane in which, in order to implement this self-loader function, in addition to a radio control device for operation, operation levers are provided on the left and right of the outrigger device. In the loading truck crane described in this document, two operation handles for operating the jack are provided vertically on one side, and these two operation handles are connected by a mechanical link mechanism, and the jack can be extended and retracted by operating either the upper or lower operation handle. Since the operation handle and the spool of the hydraulic valve are connected by a mechanical link mechanism, the position of the spool can be finely adjusted. In this regard, the configuration of raising and lowering the jack by a mechanical link mechanism can enhance the safety of jack operation compared to the configuration of raising and lowering the jack by on-off button control.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the mechanical link mechanism described in Patent Document 1, multiple support shafts are provided in the outrigger box of the outrigger device, and the link members rotate around these support shafts. In Patent Document 1, the up and down operation of the operating handle 44 causes the vertically long oscillating link 79 to rotate around the support shaft 84, and this rotational motion is transmitted through the conversion link 80 to operate the spool of the hydraulic valve. Furthermore, the operation of the operating handle 44 rotates the oscillating link 79 through link members such as the main arm 48 which rotates around the support shaft 51. However, since the multiple support shafts are fixed to the outrigger box or the like by welding, there is a problem in that it is difficult to achieve the required tolerances for positional and orientation accuracy during manufacturing. If the required tolerances are not met, these support shafts must be modified or remanufactured, which significantly impairs the efficiency of assembly work.

[0006] In view of the above circumstances, the present invention aims to provide a truck-mounted crane having a mechanical link mechanism that can tolerate dimensions outside the tolerance range when the accuracy of the support shaft that serves as the rotation center of the link member is outside the tolerance range. [Means for solving the problem]

[0007] The first invention is a truck-mounted crane that extends and retracts jacks provided on an outrigger device via a mechanical link mechanism, wherein the truck-mounted crane includes an operating handle for extending and retracting the jacks at the lower part of the outrigger device and a hydraulic valve for extending and retracting the jacks at the upper part of the outrigger device, the mechanical link mechanism converts the operation of the operating handle into the operation of the spool of the hydraulic valve, and one of the multiple link members constituting the mechanical link mechanism that transmits operation from the lower part to the upper part of the outrigger device includes a first member and a second member, and the vertical length of the link member can be adjusted by changing the combined position of the first member and the second member. The second invention is a truck-mounted crane, characterized in that, in the first invention, either the first member or the second member is provided with an engagement hole into which a support shaft for rotatably supporting the link member is loosely fitted, the first member has a first joining surface for joining with the second member, and the second member has a second joining surface for joining with the first member, and the first joining surface and the second joining surface are parallel to the support shaft. The third invention is a truck-mounted crane characterized in that, in the first invention, the first member and the second member are connected to each other by bolt fastening, and at least one of the first member or the second member is provided with two or more combinations of bolt holes necessary for the bolt fastening in a direction perpendicular to the longitudinal direction of the first member or perpendicular to the longitudinal direction of the second member. [Effects of the Invention]

[0008] According to the first invention, the link member of a mechanical link mechanism for transmitting a predetermined motion is composed of a first member and a second member, and by changing the combined position of these members and adjusting the length of the link member, even if the accuracy of the support shaft that serves as the rotation center of the link member is outside the tolerance range, the length of the link member can be adjusted to allow for dimensions outside the tolerance range. Therefore, in the assembly of the mechanical link mechanism, there is no need to modify or remanufacture the support shaft, and work efficiency is improved. According to the second invention, since the first joining surface of the first member, etc., is a surface parallel to the support shaft, the second joining surface can be shifted relative to the first joining surface by rotating it around an axis perpendicular to the first joining surface, thus easily tolerating errors in the orientation accuracy of the support shaft. According to the third invention, by providing at least one of the first member, etc., with two or more combinations of bolt holes necessary for bolt fastening, it is possible to suppress the need to change the size of the link member even when the type of truck crane is changed. [Brief explanation of the drawing]

[0009] [Figure 1]This is a front view of a link member used in a truck-mounted crane according to an embodiment of the present invention. Figure 1(A) is a front view of the assembled state of the first member and the second member, Figure 1(B) is a front view of the second member, and Figure 1(C) is a front view of the first member. [Figure 2] This is a side view of a truck-mounted crane according to an embodiment of the present invention. [Figure 3] Figure 2 is a perspective view of the outrigger device of a truck-mounted crane. [Figure 4] Figure 3 is an explanatory diagram of the outrigger device viewed from the front. [Figure 5] Figure 2 is an enlarged view from the front of the first link mechanism used in the truck-mounted crane. [Figure 6] Figure 2 is an enlarged view from the front of the third link mechanism used in the truck-mounted crane. [Figure 7] Figure 2 is an enlarged view from above of the third link mechanism used in the truck-mounted crane. [Modes for carrying out the invention]

[0010] Next, embodiments of the present invention will be described based on the drawings. However, the embodiments shown below are illustrative of a truck-mounted crane for realizing the technical concept of the present invention, and the present invention does not limit truck-mounted cranes to the following. Note that the size or positional relationship of the members shown in each drawing may be exaggerated for the sake of clarity in the explanation. Furthermore, in the following explanation, the same name and reference numeral indicate the same or similar members, and detailed explanations will be omitted as appropriate. In addition, the forward, backward, left, right, up, and down notations in this specification refer to the forward, backward, left, right, up, and down directions when an operator is operating the truck-mounted crane from the operator's cab. Furthermore, the notations "parallel," "vertical," "horizontal," and "vertical" do not need to be strictly "parallel," "vertical," "horizontal," and "vertical," but mean "effectively parallel," "effectively vertical," "effectively horizontal," and "effectively vertical" to the extent that the effect can be achieved.

[0011] <Embodiment> (Load-mounted truck crane 10) Figure 2 shows a side view of a truck-mounted crane 10 according to an embodiment of the present invention. As shown in Figure 2, the truck-mounted crane 10 has a crane device 14 mounted on the vehicle frame 15 between the driver's cab 16 and the cargo bed 12 of a general-purpose truck 11. The "vehicle body" of the truck-mounted crane 10 refers to the general-purpose truck 11.

[0012] As shown in Figure 2, the crane device 14 is equipped with outrigger devices 13 that extend outwards to the left and right. That is, the outrigger devices 13 are located between the driver's cab 16 and the cargo bed 12 when viewed from the side. Hydraulic jacks 22 are provided at the left and right ends of the outrigger devices 13. The crane device 14 is hydraulically driven by a hydraulic circuit. A group of levers for operating this hydraulic circuit is provided on both the left and right sides of the truck-mounted crane 10, and operations such as extending and retracting the jacks 22 are performed through a valve unit 24 provided on the outrigger devices 13.

[0013] Figure 3 shows a perspective view of the outrigger device 13 of the truck-mounted crane 10 of this embodiment, and Figure 4 shows an explanatory view of the outrigger device 13 from the front. Figure 4 shows the right half of the outrigger device 13.

[0014] The outrigger device 13 has a configuration in which two outrigger arms 21 extend from both the left and right ends of the outrigger box 20, and the outrigger arms 21 extend from the outrigger box 20 in the left and right directions by hydraulics. A hydraulically operated jack 22 is provided at the right end of the right outrigger arm 21 and at the left end of the left outrigger arm 21. In addition, a slewing post 23 for mounting a crane device 14 is provided in the center of the left and right sides of the outrigger box 20.

[0015] In the loading truck crane 10 according to this embodiment, the telescoping of the jack 22 provided in the outrigger device 13 is performed through the mechanical link mechanism 30. Particularly, in the loading truck crane 10 having a self-loader function, when the vehicle frame 15 is lifted, in this embodiment, the operation handle 25 constituting the mechanical link mechanism 30 is provided at the lower part of the outrigger device 13 so that an operator of the loading truck crane 10 can easily operate the operation handle 25. By operating this operation handle 25 vertically, the operator can telescope the jack 22.

[0016] The loading truck crane 10 according to this embodiment includes a hydraulic valve 26 for telescoping the jack 22 at the upper part of the outrigger device 13. This hydraulic valve 26 is one of the components of the valve unit 24.

[0017] (Mechanical link mechanism 30) The mechanical link mechanism 30 is composed of a plurality of link mechanisms. Here, the link mechanism refers to a mechanism including a joint with one or more degrees of freedom, such as a central axis, and a link member that performs operations such as rotation around this joint. In this embodiment, the mechanical link mechanism 30 has three link mechanisms: a first link mechanism 31, a second link mechanism 40, and a third link mechanism 50. And the operations of the operation handle 25 are converted into the operations of the spool 27 of the hydraulic valve 26 by these link mechanisms.

[0018] Figure 5 shows an enlarged view of the first link mechanism 31 from the front. The first link mechanism 31 includes a first support shaft 32 and a first link member 33 that rotates around the first support shaft 32. The first link member 33 is connected to the operating handle 25. The first link member 33 is also rotatably connected to the left and right connecting link members 34 at the connection point. These left and right connecting link members 34 are connected to the operating handle 25 located on the left side of the outrigger device 13, and the mechanical link mechanism 30 converts the operation of either the left or right operating handle 25 into the operation of the spool 27 of the hydraulic valve 26. Furthermore, the left and right connecting link members 34 are rotatably connected to the lower end of the second link member 42, which will be described later, at the connection point.

[0019] In the first link mechanism 31, when the operating handle 25 is operated in the E1 direction, the left and right connecting link members 34 move in the E2 direction. When the operating handle 25 is operated in the opposite direction to the E1 direction, the left and right connecting link members 34 also move in the opposite direction to the E2 direction.

[0020] Returning to Figure 4, the second link mechanism 40 will be described. The second link mechanism 40 includes a second support shaft 41 and a second link member 42 that rotates around the second support shaft 41. The second link member 42 is rotatably connected at its lower end to the left and right connecting link members 34 at their connecting portion. The second link member 42 is also connected near its upper end to a conversion link member 53, which will be described later. As shown in the figure, the second link member 42 is a link member that is longer in the vertical direction than in the horizontal direction, and transmits movement from the lower to the upper part of the outrigger device 13. The second link member 42 and the conversion link member 53 are connected such that the conversion link member 53 is rotatable around the axis of the second link member 42, and the conversion link member 53 is able to move in the axial direction of the second link member 42.

[0021] In the second link mechanism 40, when the left and right connecting link members 34 move in the E2 direction, the lower half of the second link member 42 moves in the E3 direction and the upper half of the second link member 42 moves in the E4 direction, since the second support shaft 41 is the center. When the left and right connecting link members 34 move in the opposite direction to the E2 direction, the lower half of the second link member 42 moves in the opposite direction to the E3 direction and the upper half of the second link member 42 moves in the opposite direction to the E4 direction.

[0022] Figure 6 shows an enlarged view of the third link mechanism 50 from the front, and Figure 7 shows an enlarged view of the third link mechanism 50 from above. The third link mechanism 50 includes a third support shaft 51 and a third link member 52 that rotates around the third support shaft 51. The third link mechanism 50 also includes a conversion link member 53 that connects the third link member 52 and the second link member 42. The third link member 52 is rotatably connected to the conversion link member 53 at their connection point. The third link member 52 is also rotatably connected to the spool 27 of the hydraulic valve 26 at its connection point.

[0023] In the third link mechanism 50, when the upper half of the second link member 42 moves in the E4 direction, the third link member 52 moves in the E5 direction and the spool 27 moves in the E6 direction. When the upper half of the second link member 42 moves in the opposite direction to the E4 direction, the third link member 52 moves in the opposite direction to the E5 direction and the spool 27 moves in the opposite direction to the E6 direction.

[0024] (Second link member 42) Figure 1 shows a front view of the second link member 42 used in the truck-mounted crane 10 according to this embodiment. Figure 1(A) is a front view of the assembled state of the first member 43 and the second member 44 that constitute the second link member 42, Figure 1(B) is a front view of the second member 44, which is the lower member of the second link member 42, and Figure 1(C) is a front view of the first member 43, which is the upper member of the second link member 42.

[0025] The second link member 42 is composed of two members, a first member 43 and a second member 44, and the vertical length of the second link member 42 can be adjusted by changing the combined position of these first member 43 and second member 44.

[0026] Specifically, the first member 43 is constructed by welding a steel rod and a steel plate. Both sides of the steel plate in the horizontal direction are bent. The central part of this steel plate in the horizontal direction becomes the first joining surface 45 for joining with the second member 44. The first joining surface 45 is provided with first to fourth bolt holes 49a to 49d. All bolt holes are elongated holes that are long in the horizontal direction. The first bolt hole 49a and the second bolt hole 49b, which are arranged vertically, constitute one combination of bolt holes necessary for bolting with the second member 44, and the third bolt hole 49c and the fourth bolt hole 49d constitute the other combination. The first member 43 is also provided with first engagement holes 47a and second engagement holes 47b into which a second support shaft 41 for rotatably supporting the second link member 42 is loosely fitted. In this embodiment, the distance from the first joining surface 45 to the first engagement hole 47a is equal to the distance from the first joining surface 45 to the second engagement hole 47b. Because these distances are equal, the axis of the second support shaft 41 is parallel to the first joining surface 45.

[0027] The second member 44 is constructed by welding a steel rod and a steel plate. The portion of the steel plate in which bolt holes are provided becomes the second joining surface 46 for joining with the first member 43. The second joining surface 46 is provided with a fifth bolt hole 49e and a sixth bolt hole 49f. These bolt holes are elongated holes that are long in the vertical direction. These fifth bolt hole 49e and sixth bolt hole 49f constitute the bolt hole combination necessary for bolting the first member 43 together.

[0028] The first member 43 and the second member 44 of the above configuration are fastened together by two bolts 48 to form the second link member 42. Because it consists of two members, the vertical length of the second link member 42 can be adjusted. Furthermore, the fifth bolt hole 49e and the sixth bolt hole 49f of the second member 44 are elongated vertically, which increases the adjustable length.

[0029] Since the first member 43 has a first joining surface 45 with the above configuration, and the second member 44 has a second joining surface 46 with the above configuration, the second joining surface 46 can be shifted relative to the first joining surface 45 by rotating it around an axis perpendicular to the first joining surface 45, thus easily tolerating errors in the posture accuracy of the second support shaft 41, etc.

[0030] Since the first member 43 is provided with two or more combinations of bolt holes necessary for bolt fastening, even if the model of the truck-mounted crane 10 changes, parts can be standardized between different models, and the need to change the size of the link member to match the model can be suppressed.

[0031] (others) In the above embodiment, the mechanical link mechanism 30 was composed of three link mechanisms, but it is not limited to this. The link mechanism can be one, two, or four or more.

[0032] The length of the second link member 42 was adjusted by bolting the first member 43 and the second member 44 together, but the method of adjustment is not limited to this. For example, it is also acceptable for the two members to be configured as a long screw and a nut. [Explanation of Symbols]

[0033] 10. Truck-mounted crane 13 Outrigger device 22 Jack 25 Operating handle 26 Hydraulic valves 27 Spool 30 Mechanical linkage mechanism 41. Second support axis (one of the support axes) 42 Second link member (one of the link members) 43. First component 44 Second Member 45 1st joint surface 46 Second joint surface 47a 1st engagement hole 47b Second engagement hole 49a~49f Bolt holes 1 to 6

Claims

1. A truck-mounted crane that extends and retracts jacks equipped on an outrigger device via a mechanical link mechanism, The truck-mounted crane has an operating handle for extending and retracting the jack at the bottom of the outrigger device, The outrigger device is equipped with a hydraulic valve for extending and retracting the jack at its upper part, The mechanical linkage mechanism converts the operation of the operating handle into the operation of the spool of the hydraulic valve, Among the multiple link members constituting the mechanical link mechanism, one of the link members that transmits motion from the lower to the upper part of the outrigger device is composed of a first member and a second member. The vertical length of the link member can be adjusted by changing the combined position of the first member and the second member. A truck-mounted crane characterized by its features.

2. Either the first member or the second member is provided with an engagement hole into which a support shaft for rotatably supporting the link member is loosely fitted. The first member has a first joining surface for joining with the second member, The second member has a second joining surface for joining with the first member, The first joint surface and the second joint surface are parallel to the support shaft. The truck-mounted crane according to feature 1.

3. The first member and the second member are connected to each other by bolt fastening. At least one of the first member or the second member is: Two or more combinations of bolt holes necessary for fastening the bolts are provided in a direction perpendicular to the longitudinal direction of the first member, or in a direction perpendicular to the longitudinal direction of the second member. The truck-mounted crane according to feature 1.

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