JPH0415748Y2 - - Google Patents

Description

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

[Prior art] In general, lifting magnets (hereinafter referred to as LM
It is abbreviated as ), a part of the lifted object such as rigid material is brought into contact with the suction surface formed on the bottom surface of the LM,
The LM operation of lifting the object to be lifted is performed by the magnetic force of the LM via the LM suction surface.

At this time, in such LM work, residual magnetism is generated in the lifted object, so a demagnetization function is provided to demagnetize the residual magnetism by passing an alternating positive and negative attenuating current through the LM excitation coil.

However, for a lifted object whose contact condition with the LM suction surface is not uniform, the strength of the demagnetizing field corresponding to the surface irregularities is the demagnetizing magnetomotive force, that is, the LM
The magnitude of the alternating current flowing through the exciting coil is not uniform.

For this reason, the magnetic resistance is large in the gaps between the surface irregularities, and even if the alternating current for demagnetization is not relatively small, the residual magnetism can be demagnetized to a sufficiently small value. Magnetic resistance is extremely small in the closely-contact portions, and magnetic flux concentrates in these portions, causing variations in that a sufficiently small demagnetizing field cannot be achieved unless the current is attenuated to a very small amount.

Therefore, in the past, lifting magnet devices were developed that ensured a stable demagnetization level even for lifted objects whose contact conditions with the LM adsorption surface were uneven, and that did not require the current to be attenuated to a minute level. 0.5 made of non-magnetic material on the adsorption surface to form
A spacer member having a thickness within the range of ~5 mm was provided to form a predetermined distance between the suction surface and the object to be lifted.

[Problems to be solved by the invention] However, as mentioned above, the reality is that rubber, resin, brass, etc. are used for non-magnetic spacer members, and for this reason, they are prone to wear during LM work. As a result, the thickness of the spacer member becomes thinner, making it difficult to maintain a predetermined distance between the suction surface and the object to be lifted, and as a result, there is a problem that the degaussing function deteriorates. Ta.

On the other hand, in order to prevent wear during LM work, hard spacer members (for example, SUS, Hi
-Mn, etc.), there is a drawback that when a part of the object to be lifted comes into contact with the suction surface, the hard spacer member may cause scratches on the object to be lifted. Problems may arise in the case of objects to be lifted, such as wire coils.

Therefore, in view of the above drawbacks, the technical problem of the present invention is to not only ensure a stable demagnetization level by forming a predetermined distance between the suction surface and the object to be lifted using a spacer member, but also to To provide a lifting magnet that prevents wear of the members themselves and does not cause damage to objects to be lifted.

[Means for Solving the Problems] According to the present invention, in a lifting magnet having an adsorption surface for lifting an object to be lifted and a demagnetizing function for demagnetizing residual magnetism generated in the object to be lifted, , a lifting magnet characterized in that a spacer member having a laminated structure is provided on the adsorption surface, at least one layer of the spacer member is made of a soft material, and at least the other layer is made of a hard material. It will be done.

[Function] According to the configuration of the present invention, since the spacer member in which at least one soft layer and one hard layer with mutually different magnetic properties are laminated is provided on the LM attraction surface, there is no space between the LM attraction surface and the object to be lifted. At the same time as forming a predetermined separation distance, the soft layer is brought into direct contact with the object to be lifted to prevent scratches, or the soft layer is brought into indirect contact with the object to be lifted through a hard layer to prevent wear of the spacer member itself. It can also be used as a cushion that protects the body and absorbs shocks such as when landing on the bed.

[Example] Next, an example according to the present invention will be described using the drawings.

As shown in FIGS. 1 and 2, 1 is an LM main body, and has two rows of convex portions 2, 2 extending downward from the lower surface of the LM main body 1. As shown in FIGS. At the free ends of the two rows of convex portions 2, there are LMs with tapered surfaces facing each other.
Adsorption surfaces 3, 3 are formed. On this LM adsorption surface 3, a spacer member having a two-layer structure is provided, which is formed by laminating a soft layer 4 made of a magnetic material and a hard layer 5 made of a non-magnetic material.

This ensures that the object being lifted (not shown) is always
LM suction surface 3 with a predetermined distance between
comes into contact.

At the same time, as shown in FIG. 1, when the soft layer 4 comes into indirect contact with the object to be lifted via the hard layer 5,
This soft layer 4 acts as a cushion and absorbs the impact when landing on the floor, and since the hard layer 5 hits the object to be lifted, wear of the spacer member itself can be effectively prevented.

Furthermore, as shown in Fig. 2, when the soft layer 4 comes into direct contact with the object to be lifted, the soft layer 4 not only acts as a cushion, but also comes into direct contact with the object to be lifted, so there is no damage to the object. There is no risk that this will occur.

Here, as the material constituting the soft layer 4, rubber, resin, aluminum, brass, etc. are used to prevent damage to the lifted object.

On the other hand, the hard layer 5 is most preferably non-magnetic, and is made of rubber, resin, aluminum, brass, etc.
It is preferable to be made of a wear-resistant material such as SUS and Hi-Mn.

Note that a plurality of soft layers and hard layers may be used and laminated in alternating layers. However, in order to ensure at least the minimum gap necessary to exhibit the demagnetizing function, the total thickness of the spacer member should be
It is required to be 5 mm or less.

In addition, Fig. 3 a, b, c, and d show the LM suction surface 3.
Convex portion 2 extending downward from the bottom surface of the LM body 1
If the object to be lifted comes into contact with the side surface of the convex portion 2, the side surface of the convex portion 2 may also be covered with a spacer member consisting of a soft layer 4 and a hard layer 5.

[Effects of the invention] As explained above, according to the invention, since the spacer member in which at least one soft layer and one hard layer are laminated is provided on the LM suction surface, the connection between the LM suction surface and the object to be lifted is reduced. While forming a predetermined distance between them, the soft layer can be brought into direct contact with the lifted object to prevent scratches, or indirectly contacted with the lifted object through a hard layer, so that it can be used as a spacer member. It can be used as a cushion that prevents wear and absorbs shock when landing on the floor, etc., so all you need to do is create a specified distance between the suction surface and the object being lifted to ensure a stable demagnetization level. Moreover, it is possible to provide a lifting magnet that prevents wear of the spacer member itself and does not cause damage to the lifted object.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of a lifting magnet according to an embodiment of the present invention, Fig. 2 is a longitudinal cross-sectional view of a lifting magnet according to another embodiment of the present invention, and Figs. 3 a, b, and c. , d are enlarged vertical cross-sectional views of a spacer member and an attraction surface of a lifting magnet according to another embodiment of the present invention. 1... Lifting magnet body, 2... Convex top, 3... LM adsorption surface, 4... Soft layer, 5...
Hard layer.

Claims (1)

[Claims for Utility Model Registration] 1. A lifting magnet having an adsorption surface for lifting an object to be lifted and a demagnetizing function for demagnetizing residual magnetism generated in the object to be lifted, wherein the adsorption surface is laminated. 1. A lifting magnet characterized in that a spacer member is provided, at least one layer of the spacer member is made of a soft material, and at least one other layer is made of a hard material. 2. Utility Model Registration The lifting magnet according to claim 1, wherein the one layer of the spacer member made of a soft material is made of a magnetic material. 3. Utility Model Registration The lifting magnet according to claim 1, wherein the other hard material of the spacer member is made of a non-magnetic material.