JPH0520791Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] The present invention relates to a table lift.

[Prior Art] In general, a conventional table lift is provided with a base, a table, and between the bases and the table, and lifts the table vertically to the base while maintaining a parallel relationship to the base. It is equipped with a vertical guide device such as a scissor-like link mechanism that supports the table so as to be movable in the direction, and a drive device such as a hydraulic cylinder that is provided between the base and the table and raises and lowers the table relative to the base. A scissor-like link mechanism raises and lowers the table by operating a hydraulic cylinder.

In addition, in devices where a cam is used as part of a vertical guide device between the base and the table, and the table is moved up and down by moving a cam roller that engages with this cam, the shape of the cam is adjusted to match the load of the lift. A device designed to operate with the optimum lifting force according to the situation is already known (Japanese Utility Model Publication No. 35795/1983).

[Problems to be solved by this invention] In such a table lift, when stopping the lift at a predetermined position, a position detection device such as a micro switch and a device that cuts off the power based on the signal are usually used. Therefore, it was difficult to stop the vehicle at an accurate position. On the other hand, if the lift is stopped temporarily, there is no problem, but if it is stopped for a long time, fluid leaks from the hydraulic cylinder, making it extremely difficult to keep the lift stopped at a fixed position. It was.

An object of the present invention is to provide a table lift that can accurately stop at a predetermined position and can stop at that position even if fluid leaks when the table lift stops at that position for a long time. It is to be.

[Means for Solving the Problem] In order to achieve the above object, this invention provides a base, a table, and a structure in which the table is provided between the base and the table with respect to the base. A table lift comprising a vertical guide device that movably supports the table in a vertical direction while maintaining a parallel relationship, and a drive device that raises and lowers the table, wherein the drive device is provided on the base and the table, respectively. It consists of a roller device and a cam plate having an upper surface and a lower surface that engage with the rollers of these roller devices, respectively, and is driven by a hydraulic cylinder of the drive device, and the shape of the upper surface and the lower surface of this cam plate is It is characterized in that at least both ends thereof are parallel to the surface of the table.

[Operation] The drive device has roller devices provided on the base and the table, respectively, and an upper surface and a lower surface that engage with the rollers of these roller devices, respectively, and is driven by a fluid pressure cylinder of the drive device. Since the top and bottom surfaces of this cam plate are parallel to the table surface at least at both ends, the cam plate carries the load of the table on the surfaces parallel to the table surface at both ends. When supporting the table, even if the fluid pressure decreases, the table can be stably supported at that position for a long time. In addition, if necessary, if a part is provided on the top or bottom of the cam plate that is parallel to the table surface, the table will not rise or fall in this part, so a position detection device such as a micro switch can be used to stop the table. It can be paused without placing the .

[Embodiments] Next, the present invention will be described along with embodiments shown in the accompanying drawings.

1, 2, and 3, the table lift of the present invention has a base 1 having a substantially rectangular planar shape.
, a table 2 which is placed almost on top of the base 1 and has almost the same planar shape as the base 1; a vertical guide device 3 movably supported in a direction perpendicular to the base 1 while maintaining a parallel relationship;
A driving device 4 is provided between the base 1 and the table 2 and moves the table 2 up and down with respect to the base 1.

The vertical guide device 3 may be of any known type, and in the illustrated example, it is a scissor-like link mechanism constructed by providing a pair of two links 5 and 6, one on each side, combined in an X-shape. Links 5 and 6 of the scissor-like link mechanism are pivotally connected to each other by a pin 7, the fixed end of the link 5 is pivotally connected to the base 1 by a pin 8, and the movable end engages with the table 2 via a roller 9. The fixed end of the other link 6 is pivotally connected to the table 2 with a pin 10, and the movable end is connected to the base 1 via a roller 11.
is engaged in. As is well known, the scissor-like link mechanism configured in this way moves the table 2 in a direction perpendicular to the main surface of the base 1, that is, the horizontal plane, while maintaining the parallel relationship between the table 2 and the base 1. It supports the vehicle so that it can be moved.

The driving device 4 of the present invention includes a cam plate 12 that can move to raise and lower the table 2, a roller device 13 arranged to engage with the cam plate 12, and a hydraulic cylinder that moves the cam plate 12, such as a hydraulic cylinder. It consists of a cylinder 14.

According to the present invention, the shape of the cam plate 12 is as follows:
The shape is such that the table 2 is not moved at both ends, and the table 2 is moved up and down in response to the movement of the cam plate 12 in the middle of its movement stroke. In the illustrated example, the cam plate 12 has two cam surfaces, the cam surfaces being low at one end 16 and high at the other second end 17; This is a surface parallel to the surface of table 2. First and second ends 1 having different heights
6 and 17 are connected at an inclined intermediate portion 18. Cam plates 12 are arranged inside each scissor-like link mechanism and form a pair. In order to maintain a predetermined distance between the pair of cam plates 12,
One end of each is connected by a rod 15a, and the other end is connected by a rod 15b.

The roller device 13 is a first roller device disposed on the base 1 side.
roller 19 and a second roller disposed on the table 2 side.
The first roller 19 engages with the lower surface of the cam plate 12, and the second roller 2
0 engages with the upper surface of the cam plate 12.

The hydraulic cylinder 14 has its tail end pivotally connected to the base 1, and the free end of its plunger 21 is connected to the rod 1.
5a.

In order to move the table lift of the present invention constructed in this way from the lowered position shown in FIG. 2 to the raised position shown in FIG. 3, the hydraulic cylinder 14 is operated to push out the plunger 21. Then, the cam plate 12 is moved to the right in FIG. 2 and moves between the first roller 19 and the second roller 20. The intermediate portion 18 is inclined while rotating the cam surface of the first end portion 16.
The table 2 is pushed up in a direction substantially perpendicular to the base 1 along the inclination of the cam surface.
When the cam plate 12 is further moved to the right, the second roller 20 passes the middle part 18 of the cam plate 12 and reaches the second end part 17, where the table 2 reaches its highest position.

When the second roller 20 of the roller device 13 is on the second end 17 of the cam surface of the cam plate 12, the load on the table 2 is received by the horizontal surface of the second end 17, so the table 2 is It can be kept in the elevated position stably for hours.

In the illustrated embodiment, the shape of the cam plate 2 is such that both ends of the cam plate 2 are substantially parallel to the main surface of the table 2, and the middle part is inclined to connect the two ends. The cam surface can be configured with only a horizontal surface relative to the table 2, that is, a surface that maintains the highest position of the table 2 and an inclined surface that raises and lowers the table 2, thereby simplifying the shape.
In this case, in order to stably hold the table at the lowest position, the upper end of the side wall of the base and the lower end of the side wall of the table may be in contact with each other. It is also possible to provide a stopper on either the base or the table so as to support the table 2 in a fixed position. Additionally, in the illustrated embodiment,
Although two cam plates are used, the number of cams can be increased or decreased depending on the required length of the table.

[Effects of the invention] According to this invention, by forming the cam plate with a portion whose upper and lower surfaces are parallel to the surface of the table, the table can be accurately stopped at a predetermined position for a long period of time. , extremely safe as a table lift. Moreover, it can be temporarily stopped at a predetermined position without providing any other device.

[Brief explanation of drawings]

Figure 1 is a schematic plan view of the table lift of the present invention, Figure 2 is a schematic side view showing the lowest position of the table lift in Figure 1, and Figure 3 is a schematic diagram showing the highest position of the table lift in Figure 1. FIG. 1... Base, 2... Table, 3... Vertical guide device, 4... Drive device, 12... Cam plate,
13...Roller device, 14...Hydraulic cylinder.

Claims (1)

[Claims for Utility Model Registration] (1) A base, a table, and a structure provided between the base and the table, in which the table is perpendicular to the base while maintaining a parallel relationship with the base. A table lift consisting of a vertical guide device that movably supports the table, and a drive device that raises and lowers the table, wherein the drive device includes roller devices respectively provided on the base and the table, and the rollers of these roller devices. a cam plate having an upper surface and a lower surface respectively engaged with the cam plate and driven by a hydraulic cylinder of the drive device;
A table lift characterized in that the shapes of the upper and lower surfaces of the cam plate are parallel to the surface of the table at least at both ends thereof. (2) Utility model registration claim 1, characterized in that the vertical guide device is a scissor-like link mechanism.
Table lift as described in section.