JP3243533B2 - Lifting force adjustment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lifting / lowering force adjusting device, and more particularly, to an improvement in a device capable of adjusting a lifting / lowering force of a top plate such as a wagon according to a load applied to the top plate.

[0002]

2. Description of the Related Art Heretofore, there has been known a wagon or the like installed in an office or the like, which is provided with an elevating device capable of adjusting a height position of a top plate. A wagon equipped with this elevating device includes a stationary body installed on the floor, a movable body supported on the stationary body so as to be vertically movable, and having a top plate at an upper end, and a movable body and a stationary body. And a gas spring disposed between them. In this wagon, by operating a lever attached to the gas spring, the gas spring can be appropriately extended to move the movable body up and down, and thus the height of the top plate can be adjusted.

However, in such an elevating device, since the pressure setting of the gas spring is constant, when the load applied to the top plate increases, the ascending pressure tends to be insufficient. For this reason, when the load applied to the top plate by the load becomes extremely large, there is a disadvantage that it is difficult to raise the movable body itself. Further, in this case, an auxiliary external force must be applied to push the top plate from below, which significantly reduces operability.

[0004] Japanese Utility Model Publication No. 2-40809 discloses a lifting / lowering force adjusting device capable of adjusting the lifting / lowering force of the tabletop when adjusting the height of the tabletop.
This lifting / lowering force adjusting device is provided with a support acting as a movable body on the back side of the top plate, and a gas spring having one end connected to the bottom of the desk, and between the gas spring and the support. The configuration is such that a link mechanism is provided. Here, an adjusting screw is inserted into one end of the arm constituting the link mechanism. By adjusting the axial position of the screw, the connecting position between the link mechanism and the gas spring is changed to change the position of the top plate. The lifting force is adjustable.

[0005]

However, in such a lifting / lowering force adjusting device, when the screw shaft is rotated, a tilt occurs in the axial direction of the gas spring. There is an inconvenience that the intrinsic extension pressure in the vertical direction is dispersed and the extension pressure is reduced. In addition, the inclination of the gas spring increases the moving frictional resistance of the movable body with respect to the stationary body, and hinders the smooth movement of the movable body.

[0006]

SUMMARY OF THE INVENTION The present invention has been devised in view of such inconvenience, and an object of the present invention is to prevent a vertical extension pressure of a gas spring from being reduced, and to increase and decrease a vertical acting on a movable body. An object of the present invention is to provide a lifting / lowering force adjusting device capable of reliably adjusting a force.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a stationary body, a movable body which can be raised and lowered with respect to the stationary body, and a movable body provided between the stationary body and the movable body. A lifting and lowering force adjusting device including a gas spring that applies lifting and lowering force to the movable body and a link mechanism that is connected to an advancing / retracting portion of the gas spring and adjusts the lifting and lowering force. A link arm supported by the movable body, the other end being a free end;
The link arm comprises a support member bridged between a free end side of the link arm and the stationary body, and a connecting position between the support member and the link arm is provided so as to be movable along a longitudinal direction of the link arm. Is adopted. By adopting such a configuration, it is possible to appropriately adjust the elevating pressure of the movable body by changing the connection position.

Further, the present invention provides a stationary body, a movable body provided to be movable up and down with respect to the stationary body, and provided between the stationary body and the movable body to apply a lifting force to the movable body. In a lifting / lowering force adjusting device including a gas spring and a link mechanism connected to an advancing / retracting portion of the gas spring to adjust the lifting / lowering force, the link mechanism has one end supported by the movable body and the other end. A first link arm connected to an advancing / retracting portion of the gas spring; one end of the first link arm being supported by a movable body so as to be substantially parallel to the first link arm; A second link arm extending longer than the first link arm;
A support member bridged between the free end side of the second link arm and the stationary body, and a connecting position between the support member and the second link arm is determined by a length of the second link arm; The configuration is such that it is provided so as to be movable in the direction, thereby achieving the above-mentioned object better. That is, even if the connecting position between the support member and the second link arm is changed in order to change the lifting force acting on the movable body, the gas spring is connected to the first link arm. Does not tilt. Therefore, the lifting force can be reliably adjusted according to the connection position between the support member and the second link arm without reducing the vertical extension pressure of the gas spring. Further, since the first and second link arms are formed separately, the connection position can be set over the entire second link arm, and the adjustment range of the lifting force can be expanded.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The support member according to the present invention is provided with a slit hole, and the second link arm is connected to the support member via a pin inserted through the slit hole and fixed. It is preferable to adopt a configuration in which the connection position between the second link arm and the support member is adjusted by changing the insertion position of the pin along the extending direction of the slit hole. According to this, when changing the connection position between the support member and the second link arm, it is not necessary to adjust the length of the support member, and the lifting force can be easily adjusted.

In the present invention, the link mechanism is
One end is supported by the movable body, while the other end is connected to a first link arm connected to the reciprocating portion of the gas spring, and one end is supported by the movable body so as to be substantially parallel to the first link arm. On the other hand, a second link arm extending longer than the first link arm with the other end side as a free end, and a second link arm at a position above the second link arm and similar to the second link arm A supported third link arm, a connecting arm connecting between the free end sides of the second and third link arms, and a hook between the free end side of the third link arm and the stationary body; And a connecting position between the supporting member and the third link arm is provided so as to be movable along the longitudinal direction of the third link arm. With this configuration It is possible to achieve the foregoing objects. Further, according to this configuration, since the support member can be lengthened, the change in the inclination angle of the support member with respect to the stationary body can be reduced even when the connection position between the support member and the third link arm changes. As a result, an unbalanced load acting on the connection position between the support member and the stationary body is less likely to act, and the lifting force can be more reliably adjusted.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 are schematic side views of a wagon provided with a lifting / lowering force adjusting device according to a first embodiment. Here, FIG. 1 shows a state where the movable body is located at the lowermost part, and FIG. 2 shows a state where the movable body is located at the uppermost part. In these figures, the wagon 10 includes a lower frame 11 as a stationary body, and an upper frame 12 as a movable body provided to be able to move up and down with respect to the lower frame 11.
A gas spring 13 provided between the frames 11 and 12 to apply a lifting force to the upper frame 12;
A link mechanism 14 is connected to the advancing / retracting portion 13A of the gas spring 13.

The lower frame 11 is formed by vertically and horizontally combining a plurality of frame forming bodies 11A.
8 are arranged.

The upper frame 12 is formed by vertically and horizontally combining a plurality of frame forming bodies 12A, and the upper frame 12 can be raised and lowered while being received by the lower frame 11. In addition, a top plate 20 is fixed to the upper end of the upper frame 12, whereby
As the upper frame 12 moves up and down, the height of the top plate 20 can be adjusted.

The gas spring 13 generates a constant extension pressure by the gas pressure sealed in the cylinder 13B. The upper end of the cylinder 13B of the gas spring 13 is hinged to the upper end of the upper frame 12. ing. On the other hand, the lower end side of the gas spring 13 is an advancing / retracting portion 13A, and the link mechanism 14 is connected to the advancing / retracting portion 13A. Also, cylinder 1
An operation lever 21 is provided on the upper part of the gas spring 1B.
3 is performed.

As shown clearly in FIG. 3, the link mechanism 14 has a bracket 22 fixed to a frame forming body 12A located on one side of the upper frame 12, one end of which is supported by the bracket 22, A first link arm 23 having the other end connected to the reciprocating portion 13A of the gas spring 13;
A second link arm 24, one end of which is supported by the bracket 22 so as to be substantially parallel to the second link arm 24, and a support as a support member for bridging the other end of the second link arm 24 with the lower frame 11. And a rod 25.

The bracket 22 is formed in a U-shape in a top view, and has a shaft 27 rotatably wrapped inside the bracket 22. The first and second link arms 23, 24 Are fixed at one end, respectively.
Therefore, when the extension pressure of the gas spring 13 is applied to the other end side of the first link arm 23, that is, the free end side,
The first and second link arms 23 and 24 are swingable in synchronization with each other while rotating the shaft 27.

First and second link arms 23, 24
Are formed in a long strip shape, and are arranged such that their side surfaces are parallel to each other. Here, the second
The length of the link arm 24 in the longitudinal direction is longer than the first link arm 23. The connection between the free end side of the first link arm 23 and the advancing / retracting portion 13A of the gas spring 13 is performed by connecting the free end side of the first link arm 23 to a bracket 28 fixed to the tip of the advancing / retracting portion 13A. It is done by doing. Further, a plurality of through holes 31 for adjusting the connection position P1 with the support rod 25 are formed along the longitudinal direction on the free end, which is the other end of the second link arm 24. As shown in FIG. 1, when the reciprocating portion 13A of the gas spring 13 contracts most, the first and second link arms 2
Each of the free ends 3 and 24 inclines above the bracket 22.

The lower end of the support rod 25 is
2 and is swingably supported by a frame forming body 11A located at the bottom of the lower frame 11 via the base 2. The upper end side of the support rod 25 is formed in a U-shape in a side view, and the free end side of the second link arm 24 can be sandwiched therein. The free end of the second link arm 24 is supported by the support rod 25 by hanging the pin 34 inside the support rod 25 through any one of the through holes 31. I have.
Here, by changing the position of the through hole 31 into which the pin 34 is inserted, the second link arm 24 and the support rod 2
5 can be adjusted, whereby the lifting force F1 acting on the upper frame 12 can be changed. That is, assuming that the distance between the connection position P1 and the shaft 27 is L1 and the distance between the connection position P2 of the gas spring 13 and the first link arm 23 and the shaft 27 is L2, the lifting / lowering force F1 is Extension pressure F
Since 2 is obtained by multiplying L2 / L1 which is the ratio of distances L1 and L2, lifting force F1 can be changed by changing distance L1. According to this, as the distance L1 becomes longer, that is, as the connecting position P1 is set closer to the free end of the second link arm 24, the lifting / lowering force F1 becomes smaller. A bolt 35 for adjusting the length is provided at a substantially intermediate portion of the support rod 25, and by rotating the bolt 35, the length of the support rod 25 is changed according to the position of the through hole 31 into which the pin 34 is inserted. Can be changed.

Next, adjustment of the lifting force of the lifting force adjusting device provided in the wagon 10 according to the present embodiment will be described.

When the top plate 20 is lifted when the load applied to the top plate 20 by the load is large and the lifting / lowering force F1 of the upper frame 12 is insufficient, the second link arm 24 and the support rod 25 Is moved to an appropriate position on the right side in FIG. In this state, the operation lever 21
When the gas spring 13 is unlocked by operating
The lifting / lowering force F1 acting on the upper frame 12 is surely increased without tilting in the axial direction of the gas spring 13, and with the extension of the reciprocating portion 13B of the gas spring 13, the first and second positions are set with the connection position P1 as a fulcrum. The second link arms 23 and 24 swing, and the upper frame 1
2 is pushed up, and the top board 20 rises.

Conversely, when the load applied to the top plate 20 is small, such as when there is no load, and the lifting / lowering force F1 becomes excessive, the connection position P1 between the second link arm 24 and the support rod 25 is changed to the position shown in FIG. What is necessary is just to move to an appropriate position on the left side.
In this state, when the operation lever 21 is operated to release the lock of the gas spring 13, the lifting / lowering force F1 acting on the upper frame 12 is surely reduced, so that the top plate 20 is prevented from vigorously rising. By appropriately adjusting the extension pressure of the gas spring 13 as described above, it is sufficient to apply a relatively light external force from above the top plate 20 when pushing down the top plate 20.

Therefore, according to this embodiment, even if the connecting position P1 between the second link arm 24 and the support rod 25 is changed to change the lifting / lowering force F1, the first link arm 23 is still connected to the first link arm 23. Since the gas spring 13 does not tilt in the axial direction, the vertical force F2 originally held by the gas spring 13 is not reduced and the lifting force F1 is surely adjusted according to the connection position P1. be able to.

In this embodiment, the through holes 31 are provided at a plurality of positions on the free end side of the second link arm 24. However, the present invention is not limited to this, and more through holes may be provided on the fixed end side. Good. This makes it possible to adjust the magnitude of the lifting / lowering force F1 in more steps. In particular, if the through hole 31 is provided at a position where the distance L1 is shorter than the distance L2, the elongation of the gas spring 13 can be increased. An elevating force F1 larger than the pressure F2 can be obtained.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the following description, the same reference numerals are used for the same or equivalent components as in the first embodiment, and the description thereof will be omitted or simplified.

The second embodiment is characterized in that a support plate 36 is employed as a support member instead of the support rod 25 in the first embodiment, and the adjustment of the lifting force F1 is simplified. .

That is, the lower end of the support plate 36 is fixed to a frame forming body 11A located at the bottom of the lower frame 11, and a slit hole 37 is formed at the upper end side. As shown in FIG. 4, the slit hole 37 extends in the same direction as the inclination direction of the second link arm 24 when the upper frame 12 is located at the lowermost position.
Further, it faces a plurality of through holes 31 (see FIG. 5) formed in the second link arm 24. Then, a part of the slit hole 37 and one through hole 31
The second link arm 24 is swingably supported with respect to the support plate 36 by inserting the pin 38 into the second link arm 24.

Therefore, in this embodiment, the same effects as those of the first embodiment can be obtained, and
6 and the connection position P1 of the second link arm 24 and the shaft 27
The operation of changing the distance from the robot becomes easy, and the effect of adjusting the lifting force by a simple operation can be obtained.

Next, a third embodiment of the present invention will be described with reference to FIGS. In the following description, the same reference numerals are used for the same or equivalent components as those in the first embodiment.

In the third embodiment, the structure of the link mechanism 14 in the first embodiment is changed, and the other structures are the same as those in the first embodiment.

That is, the link mechanism 14 according to the third embodiment includes a bracket 40 fixed at a position above the bracket 22, a third link arm 41 having one end supported by the bracket 40, And a connecting arm 42 for connecting between the free ends, which are the other ends of the third link arms 24 and 41, to form a parallelogram link. Here, the third link arm 4
A plurality of through-holes 31 are provided on one free end side, and the tip of the support rod 25 is connected to one of the through-holes 31 as in the first embodiment. I have. Thus, the lifting / lowering force F1 acting on the upper frame 12 can be adjusted according to the connection position P1 between the third link arm 41 and the support rod 25.

Therefore, in such an embodiment, the same operation and the same effect as in the first embodiment can be obtained, and the long supporting rod 25 can be applied. Even when the connecting position P1 between the third link arm 41 and the support rod 25 is changed, the support rod 2
5 can be reduced, and the unbalanced load caused by the magnitude of the swing angle is less likely to act on the connecting position between the support rod 25 and the lower frame 11, and the lifting force F1 is applied to the upper frame 12. The effect of being able to stably apply is obtained.

In the first embodiment, the first
And a configuration in which the second link arm is provided. However, as shown in FIG. 8, a configuration in which the first link arm is substantially omitted may be employed, thereby reducing the number of parts. Can be achieved.

[0034]

As described above, according to the present invention,
Since the link mechanism is constituted by the first link arm to which the advancing / retracting portion of the gas spring is connected and the second link arm to which the support member connected to the stationary body is adjustably connected, the axial direction of the gas spring is Does not occur, and the lifting force can be reliably adjusted according to the connection position between the support member and the second link arm without reducing the extension pressure of the gas spring.

The present invention also employs a configuration in which a slit is provided in the support member and the second link arm is connected to the support member via a pin fixed through the slit hole. Therefore, it is not necessary to adjust the length of the support member when changing the connection position between the support member and the second link arm, and it is possible to easily adjust the lifting force.

Further, since the third link arm is provided and the supporting member is connected to the third link arm, the length of the supporting member can be increased, and the biasing force acting on the connecting position with the stationary body due to the inclination of the supporting member is provided. The load is hardly applied, and a stable lifting force can be supplied.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a wagon according to a first embodiment, showing a state in which a top plate of the wagon is located at a lowermost position.

FIG. 2 is a schematic side view of the wagon, showing a state in which a top plate of the wagon is located at an uppermost position.

FIG. 3 is an enlarged perspective view of a main part showing a configuration of a link mechanism.

FIG. 4 is a schematic side view of a wagon according to a second embodiment, showing a state in which a top plate of the wagon is located at a lowermost position.

FIG. 5 is a schematic side view of the wagon showing a state in which a top plate of the wagon is positioned at the top.

FIG. 6 is a schematic side view of a wagon according to a third embodiment, showing a state in which a top plate of the wagon is located at a lowermost position.

FIG. 7 is a schematic side view of the wagon showing a state in which a top plate of the wagon is positioned at the top.

FIG. 8 is a schematic perspective view of a main part showing a modification of the first embodiment.

[Explanation of symbols]

 Reference Signs List 10 Wagon provided with lifting / lowering force adjusting device 11 Lower frame as stationary body 12 Upper frame as movable body 13 Gas spring 13A Reciprocating part 14 Link mechanism 23 First link arm 24 Second link arm 25 Support as support member Rod 36 Support plate as support member 37 Slit hole 38 Pin 41 Third link arm 42 Connecting arm

Claims (4)

(57) [Claims] A stationary body, a movable body provided to be movable up and down with respect to the stationary body, a gas spring provided between the stationary body and the movable body to apply a lifting force to the movable body, In a lifting / lowering force adjusting device including a link mechanism that is connected to an advancing / retracting portion of the gas spring and adjusts the lifting / lowering force, the link mechanism has one end supported by the movable body, and the other end connected to a free end. Link arm,
The link arm comprises a support member bridged between a free end side of the link arm and the stationary body, and a connecting position between the support member and the link arm is provided so as to be movable along a longitudinal direction of the link arm. A lifting / lowering force adjusting device, characterized in that: 2. A stationary body, a movable body provided to be movable up and down with respect to the stationary body, a gas spring provided between the stationary body and the movable body to apply a lifting force to the movable body, A lifting / lowering force adjusting device comprising: a link mechanism connected to an advancing / retracting portion of the gas spring to adjust the lifting / lowering force. The link mechanism has one end supported by the movable body and the other end connected to the gas spring. A first link arm connected to an advancing / retracting portion of the first link arm, one end of the first link arm being supported by a movable body so as to be substantially parallel to the first link arm, and the other end of the first link arm being a free end A second link arm extending longer than the second link arm, and a support member bridged between the free end side of the second link arm and the stationary body. The support member and the second link Connection position with arm Is a lifting / lowering force adjusting device provided so as to be movable along the longitudinal direction of the second link arm. 3. The support member is provided with a slit hole, and the second link arm is connected to the support member via a pin fixedly inserted through the slit hole,
3. The lifting force adjustment according to claim 2, wherein a connection position between the second link arm and the support member is adjusted by changing an insertion position of the pin along an extending direction of the slit hole. apparatus. 4. A stationary body, a movable body provided to be movable up and down with respect to the stationary body, a gas spring provided between the stationary body and the movable body to apply a lifting force to the movable body, A lifting / lowering force adjusting device comprising: a link mechanism connected to an advancing / retracting portion of the gas spring to adjust the lifting / lowering force. The link mechanism has one end supported by the movable body and the other end connected to the gas spring. A first link arm connected to an advancing / retracting portion of the first link arm, one end of the first link arm being supported by a movable body so as to be substantially parallel to the first link arm, and the other end of the first link arm being a free end A second link arm extending longer than the second link arm, a third link arm supported above the second link arm in the same manner as the second link arm, and the second and third link arms. Link arm And a support member bridged between the free end side of the third link arm and the stationary body, and the support member and the third link arm A connecting position with the third link arm is provided so as to be movable along a longitudinal direction of the third link arm.