JPH0641982Y2 - Support device for hydraulic cylinder tip in multi-stage telescopic boom - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a support device for a tip portion of a hydraulic cylinder in a multistage telescopic boom.

(Prior Art) A conventional support device A for a hydraulic cylinder tip portion in a multi-stage telescopic boom is shown in FIGS. 2 and 3 and described below.

The multi-stage telescopic boom shown in FIG. 2 is composed of a four-stage telescopic boom. The first boom 1, the second boom 2, the second boom 2, the third boom 3, the third boom 3, and the fourth boom 4 are arranged. The first boom 1 and the second boom 2 are fitted in order, and a hydraulic cylinder 5 is interposed between the first boom 2 and the second boom 2 so that the second boom 2 can be extended and retracted from the first boom 1. Between the first boom 1, the second boom 2 and the third boom 3, a suitable stretchable wire rope (not shown) is arranged, and the hydraulic cylinder 5 is provided.
A so-called wire simultaneous expansion / contraction device that expands / contracts the third boom 3 from the second boom 2 in synchronization with the expansion / contraction drive of the first boom 1 to the second boom 2 by driving is arranged. The fourth boom 4 is adapted to be manually expanded and contracted from the third boom 3. The hydraulic cylinder 5
Supports the end portion of the piston rod 6 of the hydraulic cylinder 5 to the base end portion of the first boom 1 and pivotally supports the base end portion of the cylinder tube 7 of the hydraulic cylinder 5 to the base end portion of the second boom 2. Thus, the hydraulic cylinder 5 is internally arranged in an inverted manner on the multi-stage telescopic boom. The hydraulic cylinder 5 internally arranged in the multi-stage telescopic boom is surrounded by the fourth boom 4 when the multi-stage telescopic boom is in the most contracted state, and deviates from the base end portion of the fourth boom 4 in the most extended state. Is configured. Therefore, at the tip of the cylinder tube 7 of the hydraulic cylinder 5, a support device A for the tip of the hydraulic cylinder is arranged as shown in FIG. That is, both the lever member 10 and a lever member 10 pivotally supported by a support shaft 8 provided at a proper position of the support frame 8 are fixed to the tip end portion of the cylinder tube 7 of the hydraulic cylinder 5. Supporting roller 11 for supporting the own weight of the hydraulic cylinder 5, a restricting roller 12 for restricting the rising of the hydraulic cylinder 5, and a lever roller 10 for urging the lever member 10 to one side. Spring 13
A bearing device A having a and is arranged. Lever member 10
Is urged by a spring 13 stretched between the lever member 10 and the support frame 8 so as to always rotate in the arrow X direction. Further, the lever member 10 restricts the maximum inclination angle in the XY direction by bringing both side surfaces of the support frame 8 into contact with the stopper portions 14 and 15 provided on the support frame 8, respectively. The support device A at the tip of the hydraulic cylinder in the conventional multi-stage telescopic boom thus configured operates as follows. That is, in the most extended state of the multi-stage telescopic boom, the support device A deviates from the inside of the fourth boom 4 and is located inside the base end portion of the third boom 3. Therefore, as shown by the alternate long and short dash line in FIG. 3, the lever member 10 is biased in the X direction by the spring 13, and one side surface of the lever member 10 is in contact with the stopper portion 14, that is, the lever member 10 is upright. In this state, the weight of the tip of the hydraulic cylinder 5 is supported by the support roller 11, and the rebound of the hydraulic cylinder 5 is restricted by the restriction roller 12. Next, in the fully contracted state of the multi-stage telescopic boom, the support device A is inserted into the fourth boom 4 and is located inside the tip portion of the fourth boom 4. In this case, as shown by the solid line in FIG. 3, the regulating roller 12 is engaged with the upper inner surface of the fourth boom 4 and the lever member 10 is rotated in the Y direction against the biasing force of the spring 13. . Then, the tip end of the hydraulic cylinder 5 is similarly supported by the support roller 11 and the regulation roller 12. As described above, the support device A at the tip of the hydraulic cylinder in the conventional multi-stage telescopic boom is located inside the fourth boom 4 when the multi-stage telescopic boom is in the most contracted state, and inside the third boom 3 when it is in the most extended state. Even in this case, the tip of the hydraulic cylinder 5 is supported by swinging the lever member 10.

(Problems to be Solved by the Invention) However, the bearing device A has the following problems. That is, as shown in FIG. 3, in the most extended state of the multi-stage telescopic boom, the support shaft 9 and the support roller 11 are
The straight line B connecting the respective shaft stoppers is arranged so as to be substantially orthogonal to the axis of the multistage telescopic boom.
A straight line connecting 12 and the support shaft 9 is arranged at a position deviated from the straight line B by l. For this reason, when the tip end of the cylinder tube 7 of the hydraulic cylinder 5 jumps up when the multi-stage telescopic boom is in the most extended state, the force when this rises acts on the regulation roller 12 and the force is multiplied by the length l. The generated moment acts in the direction of rotating the lever member 10 in the Y direction about the support shaft 9. When the moment acts more strongly than the biasing force of the spring 13, the lever member 10 is rotated in the Y direction. In particular, since the rotation of the lever member 10 also rotates the support roller 11, the vertical dimension in the third boom 3 and the support roller at this time
The vertical dimension of the lever member 10 supported by the control roller 11 and the regulation roller 12 has a large difference, and the tip of the hydraulic cylinder 5 swings in the third boom 3 of the multistage telescopic boom to generate a large impact noise. There is a problem of doing.

(Object of the Invention) An object of the present invention is to provide a support device for a hydraulic cylinder tip portion in a multi-stage telescopic boom that properly supports the hydraulic cylinder even if the tip portion of the cylinder tube 7 of the hydraulic cylinder 5 bounces up. To do.

(Means for Solving Problems) In order to achieve the above-mentioned object, the support device for the hydraulic cylinder tip portion of the present invention comprises a first boom, a second boom, a second boom, a third boom and a third boom. 4 Booms are sequentially inserted, and the piston rod end of the base end is pivotally attached to the first boom base end and the cylinder tube base end is pivotally attached to the second boom base end between the first and second booms. A multi-stage telescopic boom in which a hydraulic cylinder is supported in an inverted manner, and in particular, when the multi-stage telescopic boom is in the most contracted state, the fourth boom surrounds the hydraulic cylinder, and in the most extended state, the base end of the fourth boom is A support device for a hydraulic cylinder tip portion of a multi-stage telescopic boom configured to deviate from the hydraulic cylinder, wherein the cylinder tube tip portion is provided on an inner bottom surface of the fourth boom when the multi-stage telescopic boom is in the most contracted state. An arm locked shaft swingably and support member supported inwardly lower surface of the third boom, the cylinder tube tip at maximum extension condition of the multistage telescopic boom,
A biasing means that constantly biases a rotational force in one direction around the shaft stop portion to the arm, and a linear portion that connects the shaft stop portion of the arm and the tip end portion of the arm in the multi-stage in the most extended state of the multi-stage telescopic boom. A first stopper that restricts the arm biased by the biasing means to a position substantially orthogonal to the axis of the telescopic boom, and the tip of the arm and the fourth boom when the multistage telescopic boom is in the most contracted state. And a second stopper for restricting the further inclination of the arm in the inclined state by engaging the inner upper surface of the above.

(Operation) The support device for the hydraulic cylinder tip portion of the multi-stage telescopic boom of the present invention having the above-described structure operates as follows. In the fully extended state of the multi-stage telescopic boom, the weight of the hydraulic cylinder tip is supported by the support member on the inner bottom surface of the third boom. At this time, the arm is set so that the straight line connecting the tip of the arm and the shaft stop is at a position substantially orthogonal to the axis of the multi-stage telescopic boom.Therefore, there is no moment to rotate the arm when the hydraulic cylinder rebounds. Does not occur. Therefore, the rising of the hydraulic cylinder is restricted by the inner upper surface of the third boom and the arm, and the hydraulic cylinder can be supported. Next, in the fully contracted state of the multi-stage telescopic boom, the own weight of the hydraulic cylinder tip is supported by the supporting member on the inner bottom surface of the fourth boom. At this time, the arm is in a tilted state by engaging the tip of the arm with the inner upper surface of the fourth boom, but the second stopper prevents the arm from tilting any further. The upper end of the arm regulated by the second stopper and the inner upper surface of the fourth boom can regulate the hydraulic cylinder. As described above, the structure is such that the end of the hydraulic cylinder is supported by the arm and the supporting member in both the most extended state and the most contracted state of the multi-stage telescopic boom. The tip portion of the hydraulic cylinder can be reliably supported between the booms without generating impact noise.

(Embodiment) A support device for a hydraulic cylinder tip portion in a multistage telescopic boom of the present invention will be described below with reference to FIG. In FIG. 1, reference numerals 1 to 7 are the same as those shown in FIG. 2 and described in the prior art, and therefore the description thereof is omitted and the same reference numerals are used here.

In FIG. 1, C is a support device for the tip of the hydraulic cylinder in the multi-stage telescopic boom of the present invention, which is constructed as follows. Reference numeral 16 is a support frame fixed to the tip of the cylinder tube 7 of the hydraulic cylinder 5. Reference numeral 17 denotes a support member, which is a bracket 18 fixed to the lower surface of the tip of the support frame 16 and a shaft 1 provided on the bracket 18.
9 and a rotatable roller 20 fixed to the shaft 19. Reference numeral 21 is a shaft that is axially fixed to brackets 22 and 22 that are arranged and fixed on the upper surface of the support frame 16 at a substantially intermediate position. Reference numeral 23 denotes an arm, which is rotatably supported by the shaft 21, and a roller 29 is arranged at the upper end thereof via a shaft 28. Reference numeral 24 denotes a biasing means, which is stretched between a lower end portion of the arm 23 and a proper position of the support frame 16 via a shaft 25 and a support 26 and is constituted by a spring 27. It works like rotating in the direction. Reference numeral 30 denotes a first stopper fixed to the bracket 22. The arm 23 rotated in the arrow E direction by the urging means 24 in the fully extended state of the multistage telescopic boom is attached to one side surface of the arm 23. Abut the above E
The rotation of the direction is regulated. When the first stopper 30 comes into contact with one side surface of the arm 23, the straight line D connecting the swing shaft 21 of the arm 23 and the shaft 28 arranged at the upper end of the arm 23 is substantially orthogonal to the axis of the multistage telescopic boom. The position of the first stopper 30 is determined so that At this time, a slight gap S is provided between the inner lower surface of the third boom 3 and the roller 29, and when the tip end portion of the hydraulic cylinder 5 is supported in the third boom 3, the arm 23 is urged by the urging means 24. It is ensured that one side surface is in contact with the first stopper 30. 31 is the bracket 22
The second stopper 30 is fixed to the upper end of the fourth boom 4 and the roller 29 is engaged with the arm 23 against the urging means 24 in the fully contracted state of the multi-stage telescopic boom. Arrow F
This rotation is regulated when further rotating in the direction of the arrow F from the state of being tilted in the direction. In the case of this embodiment, the first stopper 30 and the second stopper 31 are composed of a single plate bent in an L shape, and are fixedly attached to the bracket 22.

The support device for the hydraulic cylinder tip portion in the multi-stage telescopic boom of the present invention constructed as described above operates as follows. In the most extended state of the multi-stage telescopic boom, the weight of the tip of the hydraulic cylinder 5 is supported by the support member 17 on the inner bottom surface of the third boom 3. At this time, the arm 23 is rotated in the direction of arrow E by the urging means 24 as shown by the alternate long and short dash line in FIG. 1 so that one side surface of the arm 23 is in contact with the first stopper 30, as described above. Since the straight line D connecting the shaft 28 and the shaft 21 is located at a position substantially orthogonal to the axis of the multi-stage telescopic boom, even if the hydraulic cylinder 5 springs up, the roller 29 contacts the inner upper surface of the third boom 3. Contact hydraulic cylinder 5
The arm 23 is not rotated by merely supporting the tip of the arm. Therefore, in the most extended state of the multi-stage telescopic boom, the tip of the hydraulic cylinder 5 is located inside the third boom 3,
It is supported by the support member 17 and the arm 23. Next, when the multi-stage telescopic boom is contracted and the fourth boom 4 is contracted into the third boom 3, the roller 29 comes into contact with the upper inner surface of the base end of the fourth boom 4 and resists the biasing means 24. Arm 23 is arrow F
When the roller 29 is rotated in the direction, the roller 29 enters the fourth boom 4, and the roller 20 of the support member 17 rides on the inner surface below the base end of the fourth boom 4 and enters the fourth boom 4. In this way, the tip of the hydraulic cylinder 5 is positioned inside the fourth boom 4, and from this time until the fully contracted state of the multi-stage telescopic boom, the rollers 29 are provided on the inner surfaces above and below the fourth boom 4. The hydraulic cylinder 5 with the rollers 20 slidingly contacting each other
It supports the tip of the. In the fully contracted state of the multi-stage telescopic boom, the weight of the tip of the hydraulic cylinder 5 supports the support member 17 on the inner bottom surface of the fourth boom 4. At this time, the arm 23 moves toward the fourth boom 4 as shown by the solid line in FIG.
The roller 29 is engaged with the inner upper surface of the and is inclined,
Since the second stopper 31 restricts the arm 23 from rotating further in the direction of arrow F, the arm 23 restricted by the second stopper 31 moves through the roller 29 even if the hydraulic cylinder 5 jumps up. The tip of the hydraulic cylinder 5 is supported by coming into contact with the inner upper surface of the fourth boom 4. Therefore, the tip of the hydraulic cylinder 5 is supported as described above in the most contracted state of the multistage telescopic boom.

It should be noted that even when the multi-stage telescopic boom is extended from the fully contracted state, it acts in the opposite manner to the fully extended state, and the process in the middle thereof can be easily assumed, so description thereof will be omitted.

Further, in the above embodiment, the multi-stage telescopic boom including the 4-stage telescopic boom has been described, but it is possible to use the multi-stage telescopic boom having the portion configured by the above-mentioned 4-stage telescopic boom at the tip side thereof at least. It is not used only for multi-stage telescopic booms consisting of only 4-stage telescopic booms.

Further, regarding the extension / contraction means of the multi-stage extension / contraction boom, the extension / contraction movement of the second boom 2 from the first boom 1 is driven by the hydraulic cylinder 5, but the extension / contraction of the third boom 3 and the fourth boom 4 is here conventional. Although it is the same as that described in the art, the means may be any of manual type, wire telescopic type, hydraulic cylinder type and the like.

(Effect of the Invention) Since the present invention is configured and operates as described above,
Even when the multi-stage telescopic boom is in the most extended state and the most contracted state, or in the middle thereof, the impact sound is generated as in the case described in the prior art, although the hydraulic cylinder tip portion can be reliably supported. This is great because it can be eliminated.

[Brief description of drawings]

FIG. 1 is an explanatory view of a support device for a hydraulic cylinder tip portion in a multi-stage telescopic boom according to the present invention, and FIGS. 2 and 3 are
It is explanatory drawing of the support device of the hydraulic cylinder front-end | tip part in the conventional multistage telescopic boom. 1: 1st boom, 2: 2nd boom, 3: 3rd boom, 4: 4th boom, 5: hydraulic cylinder, 6: piston rod, 7: cylinder tube, 17: support member, 23: arm, 24: Biasing means, 30:
1st stopper, 31: 2nd stopper

Claims (1)

[Scope of utility model registration request] 1. A first boom, a second boom, a second boom, a third boom, a third boom, and a fourth boom are sequentially fitted and inserted, and a piston rod at a base end portion between the first boom and the second boom. A multi-stage telescopic boom in which the end portion is pivotally supported on the first boom base end portion and the cylinder tube base end portion is pivotally supported on the second boom base end portion, and a hydraulic cylinder is interposed in an inverted manner, in particular, the most contracted state of the multi-stage telescopic boom. In the multi-stage telescopic boom supporting device for the hydraulic cylinder tip, the hydraulic boom is surrounded by the fourth boom, and the base end of the fourth boom deviates from the hydraulic cylinder in the most extended state. At the tip end of the cylinder tube, a support member is supported on the inner lower surface of the fourth boom when the multi-stage telescopic boom is in the most contracted state, and on the inner lower surface of the third boom when the multi-stage telescopic boom is in the most extended state, and a cylinder. An arm pivotally fixed to the tip of the tube, an urging means for constantly urging a rotational force to the arm in one direction around the axis stop, and a multi-stage telescopic boom with the arm extended in the most extended state. A first stopper for restricting the arm urged by the urging means so that a straight line connecting the shaft stop portion and the tip of the arm is located at a position substantially orthogonal to the axis of the multistage telescopic boom, and the multistage telescopic boom. A hydraulic cylinder in a multi-stage telescopic boom including a second stopper that restricts the further tilting of the arm in the tilted state by engaging the tip end portion of the arm and the inner upper surface of the fourth boom in the fully contracted state. Tip support device.