JP6082270B2 - Vacuum lift device - Google Patents

Description

  The present invention relates to a non-powered vacuum lift device that vacuum-sucks a heavy-weight transport object without power, and in particular, the arrangement and configuration of a valve device and a valve switching mechanism for automatically attaching and detaching the transport object. About.

  The non-powered vacuum lift device is a type of vacuum lift device that does not require power such as a vacuum pump to generate a vacuum for vacuum-sucking a conveyed product. This type of vacuum lift device is formed by a cylinder, a piston slidably provided in the cylinder, a suction pad that is in close contact with the surface of the conveyed product, an inner surface of the suction pad, and a surface of the conveyed product. A valve device that allows or shuts off the introduction of outside air into the vacuum chamber, and a valve device that is opened and closed as needed to lift and lower the transported object using a crane, etc. And a valve switching mechanism that alternately switches to a vacuum state in which pressure can be removed or a normal pressure state in which the conveyed product can be removed. When lifting the conveyed product, the valve mechanism provided in the valve device is closed to block the flow of outside air into the vacuum chamber, and the pressure in the vacuum chamber is maintained in a vacuum state. Further, when the conveyed product is suspended, the valve mechanism provided in the valve device is opened to allow inflow of outside air into the vacuum chamber, and the pressure in the vacuum chamber is returned to the normal pressure state.

  There are two types of valve switching mechanisms: a manual type that switches the valve mechanism manually while visually observing the working state, and an automatic type that automatically switches the valve mechanism according to the lifting and lowering operations of the piston. There is a thing. As a non-powered vacuum lift device equipped with an automatic valve switching mechanism, a valve device and a valve switching mechanism incorporated in a cylinder have been conventionally proposed (see, for example, FIG. 1 of Patent Document 1). ).

Japanese Patent Publication No.46-12781

  However, since the vacuum lift device described in Patent Document 1 has a valve device (guide cylinder) and a valve switching mechanism (tooth cylinder) incorporated in the outer cylinder, a great deal of labor is required for the assembly and maintenance of the vacuum lift device. Cost. In addition, the vacuum lift device described in Patent Document 1 uses a flexible sheet gasket as an essential component, but there is a problem in durability because the sheet gasket is easily broken during use.

  The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a vacuum lift device that is excellent in assembling and maintenance properties and excellent in durability. .

  In order to solve the above-mentioned problems, the present invention is in close contact with a cylinder, a piston slidably provided in the cylinder, and the surface of the conveyed product, and the adsorbed and adsorbed of the conveyed product according to the driving of the piston. A suction pad for detaching the conveyed product, a valve device for allowing or blocking the introduction of outside air into the vacuum chamber formed by the inner surface of the suction pad and the surface of the conveyed product, and operations for lifting and hanging the piston Each time the valve device is appropriately opened and closed, the vacuum lift device includes a valve switching mechanism that automatically switches the air pressure in the vacuum chamber alternately between a vacuum state and a normal pressure state. A valve switching mechanism is disposed outside the cylinder, and a pressing member for the valve switching mechanism is provided on the piston, so that the switching operation of the valve mechanism provided in the valve device can be performed in advance. Via a valve switching mechanism, and the configuration of performing by the pressing member.

  When the valve device and the valve switching mechanism are arranged outside the cylinder, the structure of the vacuum lift device can be simplified and the repair of the vacuum lift device can be facilitated as compared with the case where these devices and mechanisms are incorporated inside the cylinder. Can do. Further, when the switching mechanism of the valve mechanism provided in the valve device is configured to be performed using the pressing member provided on the piston, the valve mechanism of the valve device is reliably switched in accordance with the lifting / lowering operation of the piston. be able to. Furthermore, since a flexible sheet gasket is not required for generating the vacuum, the durability of the vacuum lift device can be enhanced.

  According to the present invention, in the vacuum lift device having the above-described configuration, the valve device includes a valve body in which a valve seat is formed, a movable shaft that is provided in the valve body and slides in an axial direction, and the movable shaft is always connected to the valve body. A first spring member biased in one direction; and a valve body attached to the movable shaft, wherein the valve switching mechanism has cam surfaces in which crests and troughs are alternately formed, A cam member fixed to one end of the movable shaft, a rotating roller, the rotating member abutting against the cam surface of the cam member, and the rotating member formed integrally with the rotating member. A hollow shaft that is slidably mounted on a central shaft, and an engagement means that is formed between the rotating member and the hollow shaft, and is engaged or disengaged according to the vertical movement of the hollow shaft; A sliding shaft that is slidably inserted into the hollow shaft and slides in the axial direction; A second spring member disposed between the sliding shaft and the hollow shaft and constantly biasing the sliding shaft in a direction protruding from the hollow shaft; and between the sliding shaft and the hollow shaft And a rotation mechanism that rotates the hollow shaft around the sliding shaft in accordance with the sliding of the sliding shaft.

  The valve switching mechanism opens and closes the valve mechanism provided in the valve device each time the piston is lifted or lowered, and the air pressure in the vacuum chamber automatically formed by the inner surface of the suction pad and the surface of the conveyed product Is an apparatus for alternately switching between a vacuum state in which the conveyed product can be adsorbed and a normal pressure state in which the conveyed product can be detached. In the valve switching mechanism having the above configuration, the engaging means is formed between the rotating member and the hollow shaft, and the rotating mechanism portion is formed between the hollow shaft and the sliding shaft. Opening and closing can be performed, and suction and transport of the transported object by the suction pad and separation of the suction pad from the transported transported object can be automatically repeated.

  According to the present invention, in the vacuum lift device having the above-described configuration, an interval adjusting member for adjusting an interval between the two members is provided between the sliding shaft and the pressing member.

  The sliding shaft provided in the valve switching mechanism is pressed by a pressing member that moves up and down integrally with the piston, presses the movable shaft provided in the valve device, and opens and closes the valve mechanism through the movable shaft. Do. If a gap adjusting member is provided between the sliding shaft and the pressing member, the contact timing between the pressing member and the sliding shaft when the pressing member moves downward can be adjusted. Can be appropriately adjusted, and the suction or detachment of the conveyed product by the suction pad can be performed smoothly.

  According to the present invention, since the valve device and the valve switching mechanism are arranged outside the cylinder, the structure of the vacuum lift device can be simplified as compared with the case where these devices and mechanism are incorporated inside the cylinder. Cost reduction can be achieved. Further, by arranging the valve device and the valve switching mechanism outside the cylinder, the repair of the vacuum lift device can be facilitated, so that the maintainability of the vacuum lift device can be improved. Furthermore, since the switching operation of the valve mechanism provided in the valve device is performed using a pressing member that moves up and down integrally with the piston, the valve mechanism of the valve device can be switched reliably in accordance with the vertical movement of the piston. And the reliability of the vacuum lift device can be improved. In addition, since a flexible sheet gasket is not required for generating the vacuum, the durability of the vacuum lift device can be increased.

It is a front view of the vacuum lift apparatus concerning an embodiment. It is a side view of the vacuum lift apparatus concerning an embodiment. It is a circuit diagram of the vacuum lift apparatus which concerns on embodiment when a valve apparatus is switched to an open state. It is a circuit diagram of the vacuum lift device concerning an embodiment when a valve device is changed into a closed state. It is sectional drawing of the open state of the valve apparatus which concerns on embodiment. It is sectional drawing of the closed state of the valve apparatus which concerns on embodiment. It is a perspective view which shows the 1st state of the cam mechanism which concerns on embodiment. It is a perspective view which shows the 2nd state of the cam mechanism which concerns on embodiment. It is a perspective view which shows the 3rd state of the cam mechanism which concerns on embodiment. It is a front view of the vacuum lift apparatus concerning other embodiments.

  Hereinafter, an embodiment of a vacuum lift device according to the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 to 4, a vacuum lift device 100 according to the embodiment is formed integrally with a cylinder 1, a piston 2 slidably disposed in the cylinder 1, and the piston 2, and an upper portion is a cylinder. A piston rod 2a protruding outward from the upper surface of 1, a suspension hook 3 provided at the upper end of the piston rod 2a, a pressing member 4 fixed to the upper portion of the piston rod 2a and disposed in a horizontal direction, A suction pad 6 attached to the lower part of the cylinder 1 using bolts 5 is provided. A valve mounting plate 8 is mounted on the outer surface of the cylinder 1 using bolts 7. A valve device 11 is mounted on the outer surface of the valve mounting plate 8 using bolts or the like (not shown). A valve switching mechanism 41 is attached using a bolt 10. Further, between the upper end portion of the valve device 11 and the lower surface of the pressing member 4, an interval adjusting member 12 that connects the two members is provided. Moreover, between the bottom chamber 1a of the cylinder 1 and the valve device 11, between the rod chamber 1b of the cylinder 1 and the valve device 11, and between the valve device 11 and the suction pad 6, respectively, using piping hoses 13, 14, 15 respectively. It is connected. Furthermore, a silencer 16 for preventing or suppressing the generation of intake / exhaust noise is attached to a required opening of the valve device 11. As shown in FIG. 1, the vacuum lift device 100 according to the embodiment is suspended by a crane C and transports the suction pad 6 transported object M by vacuum suction. The pressing member 4 only needs to be able to contact the interval adjusting member 12, and the planar shape thereof can be formed in an arbitrary shape such as a circle or a rectangle. Moreover, in FIG.3 and FIG.4, the code | symbol 17 has shown the air filter.

  As shown in FIGS. 1 and 2, the suction pad 6 is attached to the lower part of the cylinder 1 using bolts 5 and a skirt-like attached to the lower peripheral portion of the lower surface of the board 21 using bolts 22. It is comprised from the elastic adsorption | suction part 23. FIG. The elastic adsorption part 23 is formed using a material having rubber-like elasticity. Therefore, as shown in FIG. 1, when the tip of the suction pad 6 is brought into contact with the surface of the conveyed product M, a vacuum chamber 24 is formed between the inner surface of the suction pad 6 and the surface of the conveyed product M. . By setting the pressure in the vacuum chamber 24 to a negative pressure, the conveyed product M can be vacuum-sucked to the suction pad 6. Further, by returning the pressure in the vacuum chamber 24 to normal pressure, the conveyed product M adsorbed on the suction pad 6 can be detached.

  As shown in FIGS. 5 and 6, the valve device 11 is slidably held by the valve main body 32 in which the valve seat 31 is formed, and the upper end portion protrudes from the upper surface of the valve main body 32 to the outside. The movable shaft 33, the first spring member 34 that constantly biases the movable shaft 33 upward, and the movable shaft 33 attached to the movable shaft 33 and lowered against the elastic force of the first spring member 34. It sometimes has a valve body 35 that contacts the valve seat 31. In the present specification, the valve seat 31 and the valve body are collectively referred to as a “valve mechanism”. Air circulation holes 36 and 37 are formed in the valve main body 32 above and below the valve mechanism 32. As shown in FIGS. 1 and 2, the valve device 11 is formed by the inner surface of the suction pad 6 and the surface of the conveyed product M by switching the valve mechanism each time the piston 2 is lifted and lowered. A valve switching mechanism 41 for switching the pressure in the vacuum chamber 24 alternately to a vacuum state in which the conveyed product M can be automatically adsorbed or a normal pressure state in which the conveyed product M can be detached is attached.

  As shown in FIGS. 7 to 9, the valve switching mechanism 41 includes a cam member 42 fixed to one end of the movable shaft 33 and a rotating roller 43, and the rotating roller 43 contacts the cam surface of the cam member 42. The rotating member 44 that is in contact, the hollow shaft 46 that is slidably mounted on the central shaft 45 of the rotating member 44 that is integrally formed with the rotating member 44, and the rotating member 44 and the hollow shaft 46 The formed engaging means 47, a sliding shaft 48 inserted in the hollow shaft 46 and sliding in the axial direction of the hollow shaft 46, and a first biasing force of the sliding shaft 48 in a direction protruding from the hollow shaft 46. A two-spring member 49, and a rotation mechanism portion 50 provided between the sliding shaft 48 and the hollow shaft 46, which rotates the hollow shaft 46 around the sliding shaft 48 in response to the sliding of the sliding shaft 48. I have.

  On the cam surface of the cam member 42, as shown in FIGS. 7 to 9, two peak portions 42 a and two valley portions 42 b are alternately formed in the circumferential direction at intervals of 90 degrees. The level difference between the peak portion 42a and the valley portion 42b is set to a size that allows the valve mechanism to be opened and closed. The cam surface of the cam member 42 and the rotating roller 43 provided on the rotating member 44 are always elastically contacted by the elastic force of the second spring member 49.

  The engaging means 47 includes an engaging protrusion 47 a formed at the lower end portion of the hollow shaft 46 and an engaging concave portion 47 b formed at the upper end portion of the rotating member 44. The engagement protrusion 47a and the engagement recess 47b are engaged when the hollow shaft 46 is lowered, and the engagement is released when the hollow shaft 46 is raised.

  The second spring member 49 is disposed between the circular flange member 48 a provided at the tip of the sliding shaft 48 and the mounting bracket 9, and biases the sliding shaft 48 in a direction protruding from the hollow shaft 46. .

  As shown in FIGS. 7 to 9, the rotation mechanism 50 has a long groove-shaped cam groove 51 formed in the hollow shaft 46, one end fixed to the sliding shaft 48, and a tip inserted into the cam groove 51. And the engaging pin 52. The cam groove 51 is formed such that when the sliding shaft 48 is pushed into the hollow shaft 46, the engaging pin 52 moves to the lower end side of the cam groove 51 and the rotating roller 43 rotates 90 ° in one direction. .

  The distance adjusting member 12 is screwed into a screw hole (not shown) engraved on the end surface of the sliding shaft 48 and one end screwed to the bolt 12a and fastened to the end surface of the sliding shaft 48. And the nut 12b. When the gap adjusting member 12 is provided on the end face of the sliding shaft 48, the amount of screw 12 that is screwed onto the sliding shaft 48 is changed, so that when the pressing member 4 moves downward, the contact between the pressing member 4 and the bolt 12a. Since the contact timing can be adjusted, the opening / closing timing of the valve mechanism can be appropriately adjusted, and the suction or detachment of the conveyed product M by the suction pad 6 can be performed smoothly.

  Hereinafter, the operation of the vacuum lift device according to the embodiment will be described.

  First, in a state where the vacuum lift device 100 in which the conveyed product M is not adsorbed to the suction pad 6 is suspended from the crane C, the cylinder 1 is lowered with respect to the piston 2 due to the weight of the cylinder 1, so that the second spring The sliding shaft 48 is slid in the direction protruding from the hollow shaft 46 by the elastic force of the member 49. Further, when the engaging pin 52 provided on the sliding shaft 48 is engaged with the upper end portion of the cam groove 51 formed in the hollow shaft 46, the hollow shaft 46 also moves upward. As a result, in a state where the vacuum lift device 100 in which the conveyed product M is not adsorbed by the suction pad 6 is suspended from the crane C, the engagement protrusion 47a and the engagement recess 47b are engaged as shown in FIG. It has been released. At this time, the rotating roller 43 is dropped into the valley portion 42 b of the cam member 42. Therefore, in this state, the valve body 35 is moved away from the valve seat 31 by the elastic force of the first spring member 34, and the valve mechanism is in the open state.

  When the suction pad 6 is placed on the surface of the transported object M from this state and the tension applied to the hanging hook 3 is removed, the tip of the suction pad 6 comes into close contact with the surface of the transported object M due to the weight of the vacuum lift device 100. Is done. In this state, since the valve mechanism is in an open state, the piston 2 and the pressing member 4 that operates integrally with the piston 2 are lowered with respect to the cylinder 1 by their own weight, and the sliding shaft 48 is interposed via the interval adjusting member 12. Press down. As a result, the hollow shaft 46 is moved downward together with the sliding shaft 48, and the engagement protrusion 47 a formed on the hollow shaft 46 is engaged with the engagement recess 47 b formed on the rotating member 44. When the sliding shaft 48 is further pushed into the hollow shaft 46 from this state, the hollow shaft 46 and the rotating member 44 are integrally driven and rotated in the circumferential direction by the action of the rotating mechanism 50, as shown in FIG. As described above, the rotation roller 43 provided on the rotation member 44 rides on the peak portion 42 a of the cam surface formed on the cam member 42. As a result, the movable shaft 33 of the valve device 11 is pushed down against the elastic force of the first spring member 34, and the valve body 35 attached to the movable shaft 33 contacts the valve seat 31 formed on the valve body 32. The valve mechanism is switched to the closed state.

  When the piston 2 and the pressing member 4 are lowered by their own weight, the valve mechanism is in an open state as shown in FIGS. 3 and 5, so that the air in the bottom chamber 1a of the cylinder 1 is supplied to the valve device. 11 and the silencer 16, and a considerable amount of air is supplied to the rod chamber 1 b of the cylinder 1 via the valve device 11 and the silencer 16.

  After the suction pad 6 is brought into close contact with the surface of the conveyed product M, when the piston 2 is lifted by using the crane C, the air in the vacuum chamber 24 moves to the bottom chamber 1a of the cylinder 1 and the rod chamber 1b of the cylinder. Since the air is discharged to the outside through the silencer 16, the piston 2 moves upward with respect to the cylinder 1, and the degree of vacuum in the vacuum chamber 24 is increased. When the piston 2 moves upward with respect to the cylinder 1, the sliding shaft 48 moves in a direction protruding from the hollow shaft 46 due to the elastic force of the second spring member 49 as the pressing member 4 moves upward, The shaft 46 rotates after being moved upward by the action of the rotation mechanism unit 50. When the hollow shaft 46 moves upward, the engagement between the engagement protrusion 47a and the engagement recess 47b is released, so that the rotation member 44 does not rotate and the valve mechanism is kept closed. Therefore, it is possible to transport the transport object M by the crane C.

  After the transported object M vacuum-adsorbed on the suction pad 6 is transported to a required transport destination, when the tension applied to the hanging hook 3 is removed, the piston 2 and the pressing member 4 that operates integrally with the suspension hook 3 are moved by their own weight. Since it descends, the sliding shaft 48 of the valve switching mechanism 41 is pushed into the hollow shaft 46 by the pressing member 4 via the interval adjusting member 12. As a result, the hollow shaft 46 is also moved downward together with the sliding shaft 48, so that the engaging projection 47 a formed on the hollow shaft 46 is engaged with the engaging recess 47 b formed on the rotating member 44. When the sliding shaft 48 is further pushed into the hollow shaft 46 from this state, the hollow shaft 46 and the rotating member 44 are integrally rotated in the circumferential direction by the action of the rotating mechanism 50, as shown in FIG. As described above, the rotation roller 43 provided in the rotation member 44 is dropped into the valley 42 b of the cam surface formed on the cam member 42. At this time, since the movable shaft 33 of the valve device 11 is pushed up by the elastic force of the first spring member 34, the valve body 35 attached to the movable shaft 33 is separated from the valve seat 31 formed in the valve main body 32, The valve mechanism is switched to the open state. Therefore, as apparent from FIG. 3, the outside air introduced through the silencer 16 is supplied to the vacuum chamber 24, and the inside of the vacuum chamber 24 is in a normal pressure state.

  When the piston 2 is lifted using the crane C after the valve mechanism is switched to the open state, the sliding shaft 48 protrudes from the hollow shaft 46 due to the elastic force of the second spring member 49 as the pressing member 4 rises. Moved to. Along with this, the hollow shaft 46 also rotates after moving upward by the action of the rotation mechanism section 50. When the hollow shaft 46 moves upward, the engagement between the engagement protrusion 47a and the engagement recess 47b is released, so that the rotation member 44 does not rotate and the valve mechanism is kept open. Accordingly, the conveyed product M can be detached from the suction pad 6, and the valve device 11 and the valve switching mechanism 41 return to the state shown in FIG.

  Thus, since the vacuum lift device 100 according to the present embodiment has the valve device 11 arranged outside the cylinder 1, the structure of the vacuum lift device is simplified compared to the case where the valve device 11 is incorporated inside the cylinder 1. In addition, the repair of the vacuum lift device can be facilitated. Moreover, since the vacuum lift apparatus 100 which concerns on this embodiment performs switching operation of the valve mechanism with which the valve apparatus 11 was equipped using the press member 4 which operate | moves integrally with piston 2, it responds to the up-and-down movement of piston 2. The switching operation of the valve mechanism provided in the valve device 11 can be performed reliably. Furthermore, the vacuum lift device 100 according to the present embodiment does not require a sheet gasket when generating a vacuum state, and thus has excellent durability.

  In addition, since the vacuum lift device 100 according to the present embodiment includes the valve switching mechanism 41 in the valve device 11, the inner surface of the suction pad 6 and the conveyed product M are automatically provided each time the piston 2 is lifted and hung. The air pressure in the vacuum chamber 24 formed between the surface and the surface of the substrate can be switched alternately between a vacuum state in which the conveyed product M can be adsorbed or a normal pressure state in which the conveyed product can be detached. Work can be made more efficient.

  Further, the vacuum lift device 100 according to the present embodiment includes a gap adjusting member 12 between the sliding shaft 48 provided in the valve switching mechanism 41 and the pressing member 4 for adjusting the gap between these two members. Since it is provided, it is possible to adjust the opening / closing timing of the valve mechanism as appropriate, and the suction or desorption of the conveyed product M by the suction pad 6 can be performed smoothly.

  In the above-described embodiment, the suction pad 6 is directly attached to the cylinder 1. However, instead of such a configuration, the cylinder 1 and the suction pad 6 may be separated and attached to required positions. . For example, in the example of FIG. 10, the cylinder 1 is fixed to the center of the upper surface of the frame 61, and a plurality of (two in the example of FIG. 10) suction pads 6 are fixed to the lower surface of the frame 61. The chamber and each suction pad 6 are connected by a piping hose 62. In FIG. 10, reference numeral 63 denotes a handrail used when the frame 61 is manually moved, and reference numeral 64 denotes a pressure gauge that displays the atmospheric pressure in the cylinder 1. Since other configurations are the same as those in the above-described embodiment, the same reference numerals are given to corresponding portions, and descriptions thereof are omitted.

  INDUSTRIAL APPLICABILITY The present invention can be used for a vacuum lift device used for vacuum suction and conveyance of heavy steel plates and glass plates.

  DESCRIPTION OF SYMBOLS 1 ... Cylinder, 2 ... Piston, 2a ... Piston rod, 3 ... Hanging hook, 4 ... Pressing member, 6 ... Adsorption pad, 11 ... Valve apparatus, 12 ... Space | interval adjustment member, 21 ... Substrate, 23 ... Elastic adsorption part, 24 ... Vacuum chamber, 31 ... Valve seat, 32 ... Valve body, 33 ... Movable shaft, 34 ... First spring member, 35 ... Valve body, 36, 37 ... Air flow hole, 41 ... Valve switching mechanism, 42 ... Cam member 42a ... Cam surface peak portion, 42b ... Cam surface valley portion, 43 ... Rotating roller, 44 ... Rotating member, 45 ... Center shaft, 46 ... Hollow shaft, 47 ... Engaging means, 48 ... Sliding shaft, 48a DESCRIPTION OF SYMBOLS ... ５０ member, 49 ... 2nd spring member, 50 ... Rotation mechanism part, 51 ... Cam groove, 52 ... Engagement pin, 61 ... Frame, 62 ... Pipe hose, 63 ... Handrail, 64 ... Pressure gauge, 100 ... Vacuum Lift device, C ... Crane, M ... Conveyed goods

Claims (3)

A cylinder, a piston slidably provided in the cylinder, and a suction pad that is in close contact with the surface of the conveyed product and that adsorbs the conveyed product and detaches the adsorbed conveyed product in accordance with driving of the piston; A valve device that allows or blocks the introduction of outside air into the vacuum chamber formed by the inner surface of the suction pad and the surface of the conveyed product, and the valve device is appropriately opened and closed each time the piston is lifted or lowered. A vacuum lift device comprising a valve switching mechanism that automatically switches the air pressure in the vacuum chamber alternately to a vacuum state or a normal pressure state,
The valve device and the valve switching mechanism are arranged outside the cylinder, and a pressing member of the valve switching mechanism is provided on the piston, so that a switching operation of the valve mechanism provided in the valve device is performed. The vacuum lift device is performed by the pressing member. The valve device includes a valve body in which a valve seat is formed, a movable shaft that is provided in the valve body and slides in an axial direction, a first spring member that constantly biases the movable shaft in one direction, And a valve body attached to the movable shaft,
The valve switching mechanism has a cam surface in which crests and troughs are alternately formed, and includes a cam member fixed to one end of the movable shaft, and a rotation roller, and the rotation roller is the cam member A rotating member abutted on the cam surface, a hollow shaft slidably mounted on a central axis of the rotating member formed integrally with the rotating member, and between the rotating member and the hollow shaft Engagement means formed and engaged or disengaged according to the vertical movement of the hollow shaft, a sliding shaft slidably inserted into the hollow shaft and slidable in the axial direction, and the sliding A second spring member disposed between the moving shaft and the hollow shaft and constantly biasing the sliding shaft in a direction protruding from the hollow shaft; and provided between the sliding shaft and the hollow shaft. A rotating mechanism that rotates the hollow shaft around the sliding shaft in response to sliding of the sliding shaft. Vacuum lifting apparatus as claimed in claim 1, wherein the.   The vacuum lift device according to claim 2, further comprising an interval adjusting member for adjusting an interval between the two members between the sliding shaft and the pressing member.

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