JPH0341138Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a single-acting telescopic cylinder device used for high-altitude work platforms, telescoping antennas, telescoping lighting lights, etc. Inside the supporting outer cylinder formed by interconnecting the members in a telescopic manner,
The present invention relates to a telescoping cylinder device in which a telescoping fluid pressure cylinder made up of a plurality of cylinder members is disposed in a direction opposite to the supporting outer cylinder and can be interlocked therewith.

(Prior Art) FIG. 3 shows a conventional single-acting telescope type cylinder device, which includes, for example, four cylindrical members 11a, 11b, 11c, 11
d is a supporting outer cylinder 11 which is interconnected in a telescopic manner, and similarly four cylinder members 12a, 1.
2b, 12c, and 12d, and a telescopic fluid pressure cylinder 12 disposed inside the support outer cylinder 11 in the opposite direction to the support outer cylinder, and the maximum diameter of this hydraulic cylinder 12. The cylinder member 12a is loosely fitted into and integrally connected to the bottomed cylindrical member 11d having the smallest diameter in the support outer cylinder 11, and the cylinder member 12a has the largest diameter.
A cylinder member 12 with the smallest diameter is integrally connected to a.

(Problems to be Solved by the Invention) By the way, in the above conventional cylinder device, the cylinder member 1 of the maximum diameter in the fluid pressure cylinder 2 is placed inside the cylindrical member 11d of the minimum diameter in the support outer cylinder 11.
2a is fitted so that it cannot move in the axial direction, in other words, the cylindrical member 11d is fitted onto the cylinder member 12a and the two are always superimposed, so the length of the cylinder device when extended is There is almost no difference whether the cylindrical member 11d with the minimum diameter exists or not, and therefore, if it exists, the outer diameter will become thicker, the weight will increase, and the cost will increase. I can say that.

(Technical Means for Solving the Problems) In view of the above, the present invention has been developed to provide a cylindrical member 11 with the smallest diameter, which is considered unnecessary in conventional cylinder devices.
The purpose is to eliminate d and to improve the strength of the maximum diameter cylinder member, and the technical means of the present invention is to interconnect a plurality of cylindrical members 1a to 1c in a telescopic manner. A telescopic vertical fluid pressure cylinder 2 consisting of a plurality of cylinder members 2d to 2a is arranged inside the vertical support outer cylinder 1 in a direction opposite to the vertical support outer cylinder 1 and can be interlocked therewith. In the telescopic single-acting cylinder device, the smallest diameter cylinder member 2d of the telescopic fluid cylinder 2 is integrally connected to the largest diameter cylindrical member 1a of the supporting outer cylinder 1, and the largest diameter cylinder member 2a is integrally connected to the largest diameter cylinder member 1a of the supporting outer cylinder 1. It is slidably supported on the tubular member 1c with the smallest diameter, so that the cylinder member 2a with the largest diameter protrudes from the tip of the tubular member 1c with the smallest diameter when the cylinder device is extended, and the telescopic member 2a when the cylinder device is extended is made to be slidable. Scope type fluid pressure cylinder 2
The sliding support member 4 provided at the tip of the first stage cylinder member 2b (next to the largest diameter) is the sliding support provided at the tip of the smallest diameter cylindrical member 1c in the support outer cylinder 1. It is characterized in that it is configured to protrude upward in the axial direction of the cylinder member 2a having the largest diameter than the position of the member 5.

(Function) Due to the pressure receiving area difference, the cylinder member 2a with the largest diameter expands first, and when the cylinder member 2a reaches the extension end, the cylinder member 2b in the next stage expands, and then the cylinder in the lower stage expands. Member 2c expands. As these cylinder members expand, the upper minimum diameter cylindrical member 1 is engaged with these cylinder members.
c expands, and then the lower cylindrical member 1b expands.

During the first stage expansion, the maximum diameter cylinder member 2a further protrudes upwards from the upper stage minimum diameter cylindrical member 1c, and in this state, the upwardly protruding cylinder member 2a is inside the upper end of the uppermost stage cylindrical member 1c. A sliding support member 5 protruding from the circumferential surface contacts the outer circumferential surface of the cylinder member 2a, and a sliding support member 4 protruding from the outer circumference of the upper end of the next stage (first stage) cylinder member 2b.
is in contact with the inner circumferential surface of the uppermost cylinder member 2a, so that the uppermost cylinder member 2a is connected to the uppermost cylindrical member 1c and the next (first stage) cylinder via both sliding support members 5 and 4. It is sandwiched between the member 2b and firmly supported.

(Embodiment) An embodiment of the present invention will be described below based on FIGS. 1 and 2.

FIG. 1 shows a single-acting telescopic cylinder device used for an elevated workbench in an extended state, and FIG. 2 shows the same cylinder device in a retracted state. This telescopic cylinder device includes a support outer cylinder 1 formed by interconnecting three cylindrical members 1a, 1b, and 1c each having a circular cross section in a telescopic manner, and four cylinder members 2a. . The (lowest stage) cylindrical member 1a with the largest diameter and the (third stage) cylinder member 2d with the smallest diameter in the hydraulic cylinder 2 are integrally connected via the connecting member 3, and the hydraulic cylinder 2
The maximum diameter (basic) cylinder member 2a in
is slidably supported by the smallest diameter cylindrical member 1c at the uppermost stage of the support outer cylinder 1, and protrudes from the tip of this smallest diameter cylindrical member c when the cylinder device is extended.

Furthermore, a sliding support member 4 provided at the tip of the first stage cylinder member 2b in the hydraulic cylinder 2 when the cylinder device is fully extended as shown in FIG.
is configured to protrude upward in the internal axial direction of the largest diameter cylinder member 2a from the position of the sliding support member 5 provided at the tip of the smallest diameter cylindrical member in the support outer cylinder 1. That is, as the cylinder device extends, the proximal sliding support member 4 of the first-stage cylinder member 2b moves to the largest cylinder member by an appropriate distance from the position of the distal end sliding support member 5 of the smallest diameter cylindrical member 1c. The stopper 6 provided at a required portion of the first stage cylinder member 2b is inserted into the axially upper side of the cylinder member 2a, and the stopper 6
In this state, the maximum diameter cylinder member 2a is supported by the sliding support members 4 and 7 at two upper and lower positions from the inner peripheral surface side. A sliding member 5 is supported and located between these sliding support members 4 and 7.
As a result, the maximum diameter cylinder member 2a is supported from the outer circumferential surface side, thereby increasing the strength against the lateral load of the maximum diameter cylinder member 2a, which is likely to occur during extension, especially during maximum extension, and also preventing buckling.

Furthermore, as is clear from FIG. 1, the cylinder member 2a with the largest diameter is provided with a seal member 13 on the proximal end side of its inner peripheral surface, and the seal member 13 is provided on the side wall of the first stage cylinder member 2b. Oil communication hole 8 at the tip
is bored, and the oil inside this cylinder member 2b flows through this communication hole 8 to this cylinder member 2b.
It flows into an annular space 9 formed between the outer peripheral surface of the cylinder member 2a and the inner peripheral surface of the proximal end of the largest diameter cylinder member 2a.
The side wall of C is also provided with an oil communication hole 10 at its tip, through which the oil inside this cylinder member 2c is communicated between the outer circumferential surface of this cylinder member 2c and the inner circumferential surface of the proximal end of the first stage cylinder member 2b. It is designed to flow into an annular space formed between. The third stage (final stage) cylinder member 2d is provided with a seal member 14 on the distal end side of its outer peripheral surface, and oil does not flow into the outer peripheral surface of this cylinder member 2d. A seal member 15 is provided at the base end of the inner circumferential surface of the first stage cylinder member 2b. Therefore, according to such a configuration, the operating output of the first stage cylinder member 2b is equal to that of the cylinder member 2b in the telescopic operation of the telescopic cylinder device.
The operating output of the second stage cylinder member 2c is determined by the outer diameter of the second stage cylinder member 2c, and the operating output of the third stage minimum diameter cylinder member 2d is determined by the second stage cylinder member 2c. Therefore, changes in speed due to differences in diameter of each cylinder member, which are specific to telescopic cylinders, can be suppressed to a minimum. Incidentally, according to the conventional telescopic cylinder device shown in FIG.
2b depends on the inner diameter of the cylinder member 12a with the largest diameter, and that of the second stage cylinder member 12c depends on the inner diameter of the first stage cylinder member 12b.
Since the operating output of the third-stage cylinder member 12d is determined by the inner diameter of the second-stage cylinder member 12c, the difference between the operating speed of the first-stage cylinder member 12b and the third-stage operating speed becomes considerably large. .
In this regard, when using the cylinder device shown in FIG. 1, the operating output of the first stage cylinder member 2b depends on the outer diameter of the first stage cylinder member 2b as described above, so This means that the speed change can be reduced by the difference between the outer diameter of the first-stage cylinder member 2b and the outer diameter of the first-stage cylinder member 2b.

In FIGS. 1 and 2, reference numeral 16 denotes a guide member for preventing buckling, which is attached to the base end of the second-stage cylinder 2c in the hydraulic cylinder 2. It is adapted to slide on the inner circumferential surface of the cylindrical member 1b of the step. 1
Reference numerals 7 and 18 denote oil supply and discharge ports, through which oil is supplied and discharged to the hydraulic cylinder 2.

Incidentally, in the embodiment, the support outer cylinder 1 is formed of a cylindrical member having a circular cross section, but it may also be formed of a cylindrical member having a polygonal cross section. Further, although not shown in the drawings, suitable rotation prevention means are provided between the cylindrical members 1a, 1b, and 1c each having a circular cross section and forming the support outer cylinder 1.

(Effects of the invention) According to the invention, there is no need for the cylindrical member that is provided to overlap with the largest diameter cylinder member in conventional cylinder devices, which reduces the number of parts and reduces weight. This also has the effect of reducing costs.

In particular, according to the present invention, the sliding support member provided at the tip of the first stage (next to the maximum diameter) cylinder member in the telescopic fluid pressure cylinder when extended is the cylinder member with the smallest diameter in the support outer cylinder. Because it is configured to protrude upward in the axial direction of the cylinder member with the largest diameter than the position of the sliding support member provided at the tip of the shaped member, for example, the uppermost cylinder member is not overlapped and reinforced by the cylindrical member. However, it can be used safely by improving the strength of the boundary part (neck part) between the minimum diameter cylindrical member and the maximum diameter cylinder member, especially when using a long cylinder that is relatively weak against lateral loads. It is valid.

[Brief explanation of the drawing]

FIG. 1 is a half-longitudinal sectional view of a telescopic cylinder device in an extended state showing an embodiment of the present invention, and FIG. 2 is a half-longitudinal sectional view showing the same telescopic cylinder device in a contracted state. FIG. 3 is a longitudinal sectional view showing a conventional telescopic cylinder device. 1... Support outer cylinder, 1a, 1b, 1c... Cylindrical member, 2... Telescopic hydraulic cylinder, 2a,
2b, 2c, 2d... cylinder member, 4, 5, 7
...Sliding support member, 13, 14, 15...Seal member.

Claims (1)

[Claims for Utility Model Registration] (1) A telescopic vertical fluid pressure cylinder consisting of a plurality of cylinder members is installed inside a vertical supporting outer cylinder formed by interconnecting a plurality of cylindrical members in a telescopic manner. , in a telescoping type single-acting cylinder device arranged opposite to and interlocking with the supporting outer cylinder, the cylinder member having the smallest diameter in the fluid pressure cylinder is connected to the cylinder member having the largest diameter in the supporting outer cylinder; The cylinder member with the largest diameter is integrally connected to the member and is slidably supported with respect to the cylindrical member with the smallest diameter, so that when the cylinder device is extended, the cylinder member with the largest diameter is connected to the cylindrical member with the smallest diameter. In addition to protruding from the tip, the sliding support member provided at the tip of the first stage (next to the maximum diameter) cylinder member in the telescopic fluid pressure cylinder when extended is the smallest diameter in the supporting outer cylinder. A telescoping type single-acting cylinder device characterized in that it is configured to protrude upward in the internal axial direction of the cylinder member with the largest diameter beyond the position of the sliding support member provided at the tip of the cylindrical member. . (2) A sealing member between the final stage cylinder member (with the smallest diameter) and the cylinder member immediately before this is provided on the outer peripheral surface side of the final stage cylinder member, and the seal member is provided on the outer peripheral surface side of the cylinder member immediately before the final stage cylinder member, and The single-acting telescopic cylinder device according to claim 1, wherein a sealing material between the upper cylinder member and the upper cylinder member is provided on the inner circumferential surface of the upper cylinder member.