JPS6210673Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a lifting device, and more particularly to a lifting device suitable for use in a material testing machine or the like.

In a device that holds an object to be worked or observed from above or below, it is desirable that the holding position can be changed up or down depending on the size of the object to facilitate work or observation. Moreover, since such a function is often an additional function when viewed from the overall device, it is desirable to achieve it with a simple configuration and low cost as much as possible.

One typical example that is subject to such a request is a material testing machine. An example of a conventional material testing machine is shown in Figure 1. This testing machine is the most common fatigue testing machine, with a fixed bed 1 and guide column 2.
The specimen 4 is held between the crosshead 3 and a crosshead 3 which can move up and down along the crosshead 3. More specifically, the test specimen 4 is held between a pair of chucks 7 provided inside an actuator 5 that generates force and a load cell 6 that detects force. When installing the test piece 4, the crosshead 3 is moved up and down according to the size (length) of the test piece 4. At this time, methods for raising and lowering the crosshead 3 include a method of suspending it with a chain block or the like, and a method of using a hydraulic cylinder device 8 as shown in the figure. In any case, in this type of testing machine, the bed 1 is fixed at a high position, so depending on the size of the specimen 4, it may be inconvenient when installing it on the testing machine or observing it. .

FIG. 2 shows another type of conventional fatigue testing machine. This test machine has essentially the same construction as that of FIG. 1, and corresponding parts are designated by the same reference numerals. The tester shown in FIG. 2 differs from the tester shown in FIG. 1 in that the bed 1 is fixed at a relatively low position. This is mainly done in consideration of the ease of mounting a large test specimen, and therefore has the disadvantage that it becomes difficult to observe when a small test specimen is used. In order to eliminate this drawback, a fixed bed 1
must be able to be raised and lowered. The raising and lowering methods for this purpose include raising and lowering the bed 1 using a chain block or jack, fixing the bed 1 to the crosshead 3 and raising and lowering it together with the crosshead 3 using a hydraulic cylinder device 8 attached to the crosshead 3. A method has been considered in which a hydraulic cylinder device 8 equivalent to the hydraulic cylinder device 8 attached to the crosshead 3 is separately attached to the bed 1 and the bed 1 is moved up and down by this.

However, the first method requires a lot of labor and is also very dangerous, and it is difficult to maintain the horizontal accuracy of the bed. In the second method, the capacity of the hydraulic cylinder system must be increased due to the necessity of raising and lowering both the crosshead and the bed at the same time, thus increasing the cost. Also,
If two hydraulic cylinder devices are used as in the third method, the structure becomes complicated and the cost also increases.

A further disadvantage is that the range of vertical positions of the crosshead and bed is limited by the stroke length of the hydraulic cylinder device. Since it is not possible to move the crosshead and bed to any position on the guide support when using a hydraulic cylinder arrangement with a limited stroke length, the possible observation positions of the specimen are: within a limited area on the guide support member.

Although the above explanation has been made using a material testing machine as an example, the above-mentioned explanation can be applied to all devices that hold objects of different sizes.

Therefore, the purpose of the present invention is to provide a lifting device that can be applied to these holding devices, has a relatively simple structure, can be manufactured at low cost, and has excellent workability and safety. be.

The lifting device according to the present invention is provided with a vertical guide support member, upper and lower members each movable up and down along the guide support member, and between the upper member and the lower member, the upper and a drive device for providing vertical relative movement between the lower members, and a fixing provided on each of the upper and lower members to releasably fix the upper or lower members to the guide support member. equipment.

The drive device may include a hydraulic cylinder device, or may include a gear device having, for example, a worm and a worm gear.

As an embodiment of the present invention, a case where the present invention is applied to a fatigue testing machine will be described with reference to FIG.

The bed 11 and crosshead 13 are mounted so as to be movable up and down along a vertical guide support member 12. Further, a clamp device (not shown) is attached to the bed 11 for releasably fixing the bed 11 to the guide support member 12. A similar clamping device is also attached to the crosshead 13. A set of hydraulic cylinder devices 1 is provided between the bed 11 and the crosshead 13.
8, the cylinder portion 18a is fixed to the crosshead 13, and the piston rod portion 18b is fixed to the bed 11. The hydraulic cylinder arrangement 18 can also be omitted, for example by substituting a gear arrangement with a worm and a worm wheel. The actuator 15, load cell 16, check 17, etc. are equipped in the same way as before.

To conduct a fatigue test using the testing machine shown in FIG. 3, the position of the bed 11 is first determined based on the size of the test object (not shown). Next, the clamping device attached to the bed 11 is released while the crosshead 13 remains fixed to the guide support member 12 by the clamping device attached to the crosshead 13. If the hydraulic cylinder device 18 is operated in this state, the bed 11 will move up and down relative to the fixed crosshead 13.
When the specimen is at a desired position, for example, a position where it is easy to observe, the bed 11 is fixed to the guide support member 12 by a clamp device attached to the bed 11, and the lower end of the specimen is held by the check 17 of the bed 11. Next, the clamp device attached to the crosshead 13 is released to make the crosshead 13 movable, and the hydraulic cylinder device 18 is operated again. Then, the crosshead 13 moves up and down relative to the fixed bed 11, so it is stopped at a desired position and the chuck 1 of the crosshead 13 is moved up and down.
7 to hold the upper end of the specimen. The test will then be carried out as usual.

As described above, the elevating device of the present invention allows the bed to be raised and lowered safely and easily. In addition, the drive device represented by the hydraulic cylinder device is
Since one set is used alternatively for raising and lowering the bed and raising and lowering the crosshead, the cost is low and the construction is simple. Further, the range of the raised and lowered positions of the bed and crosshead is not limited by the stroke length of the hydraulic cylinder arrangement and can be moved to any position on the guide support member. Therefore, the hydraulic cylinder device can be made relatively short, and the observation position of the test specimen can be selected from a wide range.

Although we have described the case where the present invention is applied to a fatigue testing machine as an example, the lifting device according to the present invention can also be applied to other testing machines, such as a static tensile testing machine, and the work or observation target can be viewed from above and below. It can also be applied to all holding devices. At this time, by being able to raise and lower the position of the bed, it is not only easier to observe the object, but also easier to work with.

[Brief explanation of drawings]

FIG. 1 is a front view showing an example of a conventional fatigue testing machine. FIG. 2 is a front view showing another example of a conventional fatigue testing machine. FIG. 3 is a front view showing an embodiment in which the lifting device according to the present invention is applied to a fatigue testing machine. 11... Lower member (bed), 12... Guide support member, 13... Upper member (crosshead), 1
8... Drive device (hydraulic cylinder device).

Claims (1)

[Claims for Utility Model Registration] 1. A vertical guide support member, upper and lower members each movable up and down along the guide support member, and provided between the upper member and the lower member, a drive device for providing vertical relative movement between the upper and lower members; and a drive device provided on each of the upper and lower members, releasably fixing the upper or lower member to the guide support member. Lifting device with fixing device for lifting. 2 Utility Model Registration The lifting device according to claim 1, wherein the driving device is a hydraulic cylinder device. 3. The lifting device according to claim 1, wherein the drive device is a gear device.