Steel coil placing rack for iron groove forming machine

Abstract

The invention relates to the technical field of placing racks, in particular to a steel coil placing rack for an iron groove forming machine, which comprises a base, a fixed rod vertically arranged on the upper end surface of the base, a rotating sleeve rotatably arranged on the fixed rod, and at least three support rods annularly arranged on the rotating sleeve at equal intervals, the at least three supporting vertical rods are annularly arranged on the upper end face of the base at equal intervals and located on the outer side of the supporting rod, the supporting transverse plates are arranged on the upper end faces of the supporting vertical rods correspondingly, the fixing bases are arranged on the upper end faces of the supporting transverse plates correspondingly, and the sliding holes are formed in the fixing bases correspondingly; the sliding holes are formed in the fixed seats, the sliding rods are arranged on the fixed seats in a sliding mode and located in the sliding holes, the linkage kidney-shaped holes are formed between the sliding rods and the fixed seats and located in the sliding holes, and the linkage push rods are arranged on the upper end faces of the sliding rods and are in clearance fit with the linkage kidney-shaped holes.

Description

Technical Field

[0001] The invention relates to the technical field of placement racks, and in particular to a steel coil placement rack for an iron trough forming machine. Background Art

[0002] An umbrella is composed of ribs, a stick, an umbrella cover, and an umbrella frame. The umbrella frame is connected to the ribs and the stick by multiple iron troughs, and the positions of the iron troughs and the ribs are corresponding. In order to prevent the ribs from being squeezed against the iron troughs after the umbrella is folded and to reduce the overall volume of the umbrella after folding, grooves are opened on the iron troughs to cooperate with the ribs to prevent the ribs from being squeezed against the iron troughs after the umbrella is folded. The iron troughs are usually produced using an iron trough forming machine.

[0003] ‌Iron trough forming machine is a kind of equipment specially used for processing iron trough parts. Its working principle mainly includes stamping and extrusion. It is necessary to put the rolled steel coil blank into the machine and use multiple punching heads or extrusion heads to stamp or extrude the blank to form the required parts under the extrusion. This processing method has the advantages of high efficiency, precision and energy saving, and can meet the needs of large-scale and high-quality trough parts processing.

[0004] like Figure 1 As shown, the steel coil placement rack in the prior art includes a fixed rod a1 vertically set on the ground, a rotating sleeve a2 rotatably set on the fixed rod a1, four support rods a3 annularly equidistantly set on the rotating sleeve a2, and a steel coil a4 placed on the four support rods a3. The steel coil is inserted downward from the top of the fixed rod until the four support rods support the lower end surface of the steel coil. When the iron trough forming machine pulls out the steel coil, the steel coil is pressed on the support rod by its own gravity. As the steel coil is pulled, the support rod rotates on the fixed rod through the rotating sleeve, so that the steel coil rotates circumferentially as it is pulled out.

[0005] However, the support frame can only support the lower end of the steel coil. During the unwinding process, the unwinding tension of the steel coil gradually increases as the steel coil decreases. At this time, the side end of the steel coil cannot be supported, so the unwinding of the steel coil cannot be reduced. The unwinding steel coil is easy to fall from the placement frame, which can easily cause the steel coil to be bumped and deformed, affecting the processing effect of the iron trough frame. Summary of the invention

[0006] The purpose of the present invention is to provide a steel coil placement rack for an iron trough forming machine in view of the defects and shortcomings of the prior art.

[0007] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a steel coil placement rack for an iron trough forming machine, comprising a base, a fixed rod vertically arranged on the upper end surface of the base, a rotating sleeve rotatably arranged on the fixed rod, at least three support rods annularly equidistantly arranged on the rotating sleeve for placing steel coils, and also comprising at least three support vertical rods annularly equidistantly arranged on the upper end surface of the base and located on the outside of the support rods, support horizontal plates respectively arranged on the upper end surfaces of each of the support vertical rods, fixed seats respectively arranged on the upper end surfaces of each of the support horizontal plates, and respectively opened on each The sliding holes on the fixing seat, sliding rods slidably arranged on the fixing seat and located in the sliding holes for moving closer to or away from the end of the support rod in the sliding holes when driven by external force, pushing springs respectively arranged between the sliding rods and the fixing seats and located in the sliding holes for pushing the sliding rods to move closer to the end of the support rod in the sliding holes, linkage waist holes opened on the upper end surfaces of the fixing seats and connected to the sliding holes, and linkage push rods arranged on the upper end surfaces of the sliding rods and gap-matched with the linkage waist holes for driving the sliding rods to move away from the end of the support rod in the sliding holes; A limit flap can be rotatably arranged on the upper end surface of each fixing seat and located on one side of the linkage waist hole, and the length of the limit flap is greater than the width of the linkage waist hole.

[0008] A further improvement is that each of the linkage push rods is obliquely arranged on the upper end surface of the sliding rod.

[0009] A further improvement is that the inclination angle between the linkage push rod and the fixing seat is 60°-70°.

[0010] A further improvement is that a smooth layer is provided on the end surface of each sliding rod close to the fixed rod.

[0011] A further improvement is that: the end surface of each sliding rod close to the fixed rod is provided with an arc surface, and the arc surface is provided on the smooth layer.

[0012] A further improvement is that the smooth layer is a polytetrafluoroethylene layer.

[0013] A further improvement is that: an abutment roller is rotatably provided on the end surface of each sliding rod close to the fixed rod, and the abutment roller is a nylon roller.

[0014] Further improvements are: an auxiliary sliding groove is provided on the lower end surface of the sliding rod, at least one arc-shaped placement groove is provided on the fixed seat, balls are provided in each arc-shaped placement groove on the fixed seat, the auxiliary sliding groove is provided along the length direction of the sliding rod, and several arc-shaped placement grooves are equidistantly arranged along the length direction of the fixed seat.

[0015] A further improvement is that a positioning ring block is provided on the fixing rod in a liftable manner.

[0016] After adopting the above technical scheme, the beneficial effect of the present invention is as follows: when the steel coil is placed on the support rod, the pushing spring pushes the sliding rod in the sliding hole to approach the end of the support rod, so that the sliding rod abuts against the outer side of the steel coil; when the steel trough forming machine continuously pulls the steel coil for unwinding, the support rod is driven to rotate on the fixed rod by the weight of the steel coil itself; during the unwinding process, the steel coil gradually decreases, and the pushing spring continuously pushes the sliding rod to abut against the outer side of the steel coil, thereby preventing the steel coil from unwinding on the support rod, and will not cause the unwinding steel coil to scatter from the placement rack, and will not easily cause the steel coil to be bumped and deformed, thereby affecting the processing effect of the iron trough bone.

[0017] Further effect: although the unwinding tension of the steel coil increases during the unwinding process, the push spring maintains the pushing effect on the sliding rod, and the unwinding range of the steel coil can be limited when the steel coil is unwinding.

[0018] Further effect: Compared with a directly vertically set linkage push rod, an inclined linkage push rod can allow the thrust to be better transmitted from the linkage push rod to the sliding rod when the hand pushes the linkage push rod to move toward the end of the push spring in the linkage waist hole, thereby improving the control effect of the linkage push rod by the operator's hand and allowing the hand to push the linkage push rod more effortlessly.

[0019] Further effect: the angle formed between the inclined linkage push rod and the fixed seat can be used for the limit flap to limit the position. When the limit flap is engaged with the inclined linkage push rod, the upper side angle of the limit flap abuts against the inclined surface of the linkage push rod, and due to the reaction force generated by the contraction of the push spring, the linkage push rod is squeezed against the upper side angle of the limit flap, generating pressure between the limit flap and the upper end surface of the fixed seat, so that the limit flap is pressed more firmly against the upper end surface of the fixed seat.

[0020] Further effect: the arrangement of the arc surface and the smooth layer can reduce the friction between the sliding rod and the side end surface of the steel coil when the push spring pushes the sliding rod to abut against the side end surface of the steel coil, thereby reducing the phenomenon of the sliding rod scratching the surface of the steel coil.

[0021] Further effect: the diameter of the positioning ring block is set and selected according to the inner diameter of the steel coil. The positioning ring block is mainly used to place the steel coil. The inner diameter of the steel coil is sleeved on the outer diameter of the positioning ring block through the position of the positioning ring block, so that when the steel coil is placed on the support rod, the central axis of the steel coil can correspond to the fixed rod as much as possible, reducing the phenomenon of unstable sliding rod extrusion caused by the displacement of the steel coil placement. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 It is a structural schematic diagram of a support frame in the prior art; Figure 2 It is a top view of the base, the fixing rod and the supporting rod in the present invention; Figure 3 It is a front view cutaway view of the base, the fixing rod and the supporting rod in the present invention; Figure 4 is a front view cutaway view of the fixing seat in the present invention; Figure 5 It is a top view of the fixed seat and the sliding rod in the present invention; Figure 6 It is another structural top view of the fixed seat and the sliding rod in the present invention; Figure 7 It corresponds to Figure 4 Enlarged view of part A.

[0024] Explanation of the reference numerals in the accompanying drawings: base 1, fixed rod 2, rotating sleeve 3, support rod 4, support vertical rod 5, support horizontal plate 6, fixed seat 7, sliding hole 8, sliding rod 9, pushing spring 10, linkage waist hole 11, linkage push rod 12, limiting flap 13, smooth layer 14, arc surface 15, abutting roller 16, auxiliary slide groove 17, arc placement groove 18, ball 19, positioning ring block 20. DETAILED DESCRIPTION

[0025] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0026] See also Figures 2 to 7As shown, the technical solution adopted in this specific embodiment is: a steel coil placement rack for an iron trough forming machine, comprising a base 1, a fixed rod 2 vertically arranged on the upper end surface of the base 1, a rotating sleeve 3 rotatably arranged on the fixed rod 2, at least three support rods 4 for placing steel coils arranged annularly and equidistantly on the rotating sleeve 3, and also comprising at least three support vertical rods 5 annularly and equidistantly arranged on the upper end surface of the base 1 and located on the outside of the support rods 4, support horizontal plates 6 respectively arranged on the upper end surfaces of each support vertical rod 5, fixed seats 7 respectively arranged on the upper end surfaces of each support horizontal plate 6, and sliding plates respectively opened on each fixed seat 7. The movable hole 8, the sliding rod 9 which is slidably arranged on the fixed seat 7 and located in the sliding hole 8 and is used to move closer to or away from the end of the support rod 4 in the sliding hole 8 when driven by external force, the pushing spring 10 which is respectively arranged between each sliding rod 9 and each fixed seat 7 and located in the sliding hole 8 and is used to push the sliding rod 9 to move closer to the end of the support rod 4 in the sliding hole 8, the linkage waist hole 11 which is opened on the upper end surface of each fixed seat 7 and is connected with the sliding hole 8, and the linkage push rod 12 which is arranged on the upper end surface of the sliding rod 9 and is clearance-matched with the linkage waist hole 11 and is used to drive the sliding rod 9 to move away from the end of the support rod 4 in the sliding hole 8; A limit flap 13 is rotatably provided on the upper end surface of each fixing seat 7 and located at one side of the linkage waist hole 11 . The length of the limit flap 13 is greater than the width of the linkage waist hole 11 .

[0027] The diameter of the rotating sleeve 3 is smaller than the inner diameter of the steel coil; the rotating sleeve 3 is rotatably connected to the fixed rod 2 through a bearing, and a universal wheel can also be set on the lower end surface of the support rod 4, and the lower end surface of the universal wheel rolls on the upper end surface of the base 1, and the support rod 4 and the steel coil are supported by the universal wheel; there are four supporting vertical rods 5, and the four supporting vertical rods 5 are arranged in a ring and equidistantly on the upper end surface of the base 1, and the number of supporting cross plates 6 is the same as the number of supporting vertical rods 5; the inner diameter formed between each supporting cross plate 6 and the middle end of the base 1 is larger than the outer diameter formed between each supporting rod 4 and the middle end of the base 1. This arrangement can prevent the outer side of the support rod 4 from contacting the inner side of the supporting cross rod when the support rod 4 rotates around the fixed rod 2; the number of fixed seats 7 is the same as the number of supporting The number of the transverse plates 6 is the same, and the sliding holes 8 are provided on each fixed seat 7, and the sliding holes 8 are provided along the length direction of the fixed seat 7; the sliding holes 8 are opened from one side of the fixed seat 7, extending to the tail of the fixed seat 7 and not opened; the pushing spring 10 can be fixedly arranged between the sliding rod 9 and the fixed seat 7, or can directly abut between the sliding rod 9 and the fixed seat 7; the linkage waist hole 11 is provided along the length direction of the fixed seat 7; the lower end surface of the linkage push rod 12 is arranged on the upper end surface of the sliding rod 9, and can be fixedly connected to the upper end surface of the sliding rod 9 by welding or bonding, and the middle part of the linkage push rod 12 can be slidably arranged in the linkage waist hole 11, and the upper part of the linkage push rod 12 passes through the linkage waist hole 11 and is located above the fixed seat 7; Two fixing blocks are arranged on the upper end surface of the fixing seat 7 at one side of the linkage waist hole 11, and the limit flap 13 is hingedly connected to the two fixing blocks through a rotating shaft; the setting position of the limit flap 13 is as shown in FIG. Figure 5 As shown, it is relatively far from the support rod 4; the length of the limit flap 13 is the length that can directly cover the entire linkage waist hole 11 when the limit flap 13 is flipped to cover the linkage waist hole 11. The length is set according to the width of the linkage waist hole 11 and the position of the two fixing blocks on the upper end surface of the fixing seat 7. In this embodiment, the length of the limit flap 13 is preferably set to be greater than the width of the fixing seat 7. After the limit flap 13 covers the linkage waist hole 11, one end of the limit flap 13 can protrude from one side of the fixing seat 7, which is convenient for the hand to reset and flip the limit flap 13. The setting of the linkage push rod 12 in the linkage waist hole 11 can also play a role in the sliding position of the sliding rod 9 in the sliding hole 8, preventing the sliding rod 9 from detaching from the sliding hole 8.

[0028] Each linkage push rod 12 is obliquely arranged on the upper end surface of the sliding rod 9 .

[0029] The inclination angle between the linkage push rod 12 and the fixing seat 7 is 60°-70°. The inclination direction of the linkage push rod 12 is from top to bottom, and gradually tilts downward toward the outer diameter of the base 1.

[0030] The end surface of each sliding rod 9 close to the fixed rod 2 is provided with a smooth layer 14 .

[0031] The end surface of each sliding rod 9 close to the fixed rod 2 is provided with an arc surface 15 , and the arc surface 15 is provided on the smooth layer 14 .

[0032] The smooth layer 14 is a polytetrafluoroethylene layer. The smooth layer 14 is a coating applied on the sliding rod 9, or a polytetrafluoroethylene block can be directly set and fixed on the sliding rod 9, and the arc surface 15 is set on the polytetrafluoroethylene block. Polytetrafluoroethylene has the characteristics of being very smooth. Polytetrafluoroethylene also has excellent corrosion resistance, self-lubrication and non-stick properties, and has good wear resistance, pressure resistance and low friction coefficient. The smooth layer 14 can also be a polyimide layer or a polyetherketone layer or a polyphenylene sulfide layer or a polyperfluoroethylene propylene layer. These materials are similar to polytetrafluoroethylene in terms of smoothness and chemical corrosion resistance, and are suitable for application scenarios requiring high smoothness and chemical corrosion resistance.

[0033] The end surface of each sliding rod 9 close to the fixed rod 2 is rotatably provided with an abutment roller 16, and the abutment roller 16 is a nylon roller. Nylon has a certain elasticity and can adapt to the slight unevenness of the workpiece surface to avoid excessive cutting or damage to the workpiece surface. In the case where the smooth layer 14 and the curved surface 15 are not provided, an abutment roller 16 can be provided on the sliding rod 9 to contact the side end surface of the steel coil, which can also reduce the friction between the sliding rod 9 and the side end surface of the steel coil and reduce the phenomenon of the sliding rod 9 scratching the surface of the steel coil; an installation opening is provided on the end surface of the sliding rod 9 close to the fixed rod 2, and the upper and lower ends of the abutment roller 16 can be rotatably set in the installation opening by rotation. When the abutment roller 16 is installed in the installation opening, one end surface of the abutment roller 16 is exposed outside the sliding rod 9 so that the abutment roller 16 can contact the side end surface of the steel coil. An auxiliary slide groove 17 is provided on the lower end surface of the sliding rod 9, and at least one arc-shaped placement groove 18 is provided on the fixed seat 7. A ball 19 is provided in each arc-shaped placement groove 18 on the fixed seat 7. The auxiliary slide groove 17 is provided along the length direction of the sliding rod 9, and a plurality of arc-shaped placement grooves 18 are equidistantly provided along the length direction of the fixed seat 7. The center position of the arc-shaped placement groove 18 and the center position of the ball 19 are no longer in the same point. The arc-shaped placement groove 18 is a semicircular arc. The fixed seat 7 can be made of plastic material or other materials with deformation function. When installing the ball 19, the ball 19 is aligned with the arc-shaped placement groove 18 and pressed down, so that the ball 19 is stuck in the arc-shaped placement groove 18, and the ball 19 can roll in the arc-shaped placement groove 18, and the position of the ball 19 is limited by the arc surfaces on both sides of the arc-shaped placement groove 18, so as to reduce the phenomenon of the ball 19 slipping off.

[0034] A positioning ring block 20 is provided on the fixing rod 2 so as to be liftable.

[0035] The working principle of the present invention is as follows: when it is necessary to place the steel coil on the support rod 4 for support, each linkage push rod 12 is first driven by the hand, thereby driving each sliding rod 9 to move away from the end of the support rod 4 in the sliding hole 8. When the linkage push rod 12 moves outward to a position that exceeds the position of the limit flap 13, the limit flap 13 is flipped to cover the linkage waist hole 11, and then the hand control of the linkage push rod 12 is removed, and the movement direction of the sliding rod 9 to the end of the support rod 4 is limited by the limit flap 13. There is no need for the hand to continuously push the linkage push rod 12. After each sliding rod 9 is moved away from and fixed to the end of the support rod 4, the positioning ring block 20 is first inserted from above the fixed rod 2 until the lower end of the positioning ring block 20 abuts against the rotating sleeve 3, and then the steel coil is inserted from above the fixed rod 2 and placed on the support rod 4. The inner diameter of the steel coil is sleeved on the outer diameter of the positioning ring block 20 through the position of the positioning ring block 20, thereby When the steel coil is placed on the support rod 4, the central axis of the steel coil can be made to correspond to the fixed rod 2 as much as possible, and then the multiple linkage push rods 12 are pushed again, and the limit flap 13 is flipped to the original position until the limit flap 13 no longer limits the linkage push rod 12, and then the hand releases the push of the linkage push rod 12 to allow the push spring 10 to release the elastic potential energy, and push the sliding rod 9 in the sliding hole 8 to approach the end of the support rod 4, so that the sliding rod 9 abuts against the outer side of the steel coil. When the steel trough forming machine continuously pulls the steel coil for unwinding, the support rod 4 is driven to rotate on the fixed rod 2 by the weight of the steel coil itself. During the unwinding process, the steel coil gradually decreases, and the push spring 10 continues to push the sliding rod 9 to abut against the outer side of the steel coil, thereby preventing the steel coil from being unwound on the support rod 4, and will not cause the unwound steel coil to scatter from the placement rack, and it is not easy to cause the steel coil to be bumped and deformed to affect the processing effect of the iron trough bone; Compared with the linkage push rod 12 being directly arranged vertically, the linkage push rod 12 being arranged obliquely can allow the thrust to be better transmitted from the linkage push rod 12 to the sliding rod 9 when the linkage push rod 12 is pushed by the hand to move toward the end of the push spring 10 in the linkage waist hole 11, so as to improve the control effect of the linkage push rod 12 by the operator's hand, and enable the hand to push the linkage push rod 12 with more effort; The angle formed between the inclined linkage push rod 12 and the fixed seat 7 can be used for the limit flap 13 to limit the position. When the limit flap 13 is engaged with the inclined linkage push rod 12, the upper side angle of the limit flap 13 abuts against the inclined surface of the linkage push rod 12, and due to the reaction force generated by the contraction of the push spring 10, the linkage push rod 12 is squeezed on the upper side angle of the limit flap 13, generating pressure between the limit flap 13 and the upper end surface of the fixed seat 7, so that the limit flap 13 is pressed more firmly on the upper end surface of the fixed seat 7; The arrangement of the arc surface 15 and the smooth layer 14 can reduce the friction between the sliding rod 9 and the side end surface of the steel coil when the push spring 10 pushes the sliding rod 9 to abut against the side end surface of the steel coil, thereby reducing the phenomenon of the sliding rod 9 scratching the surface of the steel coil.

[0036] The invention is intended to protect the structure of the product. The model of each component is not the content of the invention, and it is also a known technology. Any component on the market that can achieve the above-mentioned functions of the invention can be selected and applied as a steel coil placement rack for an iron trough forming machine. Therefore, the model and other parameters of the component are not described in detail in the invention. The contribution of the invention lies in the scientific combination of the components.

[0037] The above shows and describes the basic principles and main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents. Anything not described in detail in the present invention is a well-known technology of those skilled in the art.

Claims

1. A steel coil placement rack for an iron trough forming machine, comprising a base, a fixed rod vertically arranged on the upper end surface of the base, a rotating sleeve rotatably arranged on the fixed rod, and at least three supporting rods annularly equidistantly arranged on the rotating sleeve for placing steel coils, characterized in that: The invention also comprises at least three supporting vertical rods which are equidistantly arranged on the upper end surface of the base and located outside the supporting rod, supporting horizontal plates which are respectively arranged on the upper end surface of each supporting vertical rod, fixing seats which are respectively arranged on the upper end surface of each fixing seat, sliding holes which are respectively arranged on each fixing seat, sliding rods which are slidably arranged on the fixing seat and located in the sliding holes and are used to move closer to or away from the end of the supporting rod in the sliding holes when driven by external force, pushing springs which are respectively arranged between each sliding rod and each fixing seat and located in the sliding holes and are used to push the sliding rods to move closer to the end of the supporting rod in the sliding holes, linkage waist holes which are arranged on the upper end surface of each fixing seat and are connected with the sliding holes, and linkage push rods which are arranged on the upper end surface of the sliding rod and are gap-matched with the linkage waist holes and are used to drive the sliding rods to move away from the end of the supporting rod in the sliding holes; A limit flap can be rotatably arranged on the upper end surface of each fixing seat and located on one side of the linkage waist hole, and the length of the limit flap is greater than the width of the linkage waist hole.

2. The steel coil placement rack for an iron trough forming machine according to claim 1, characterized in that: Each of the linkage push rods is obliquely arranged on the upper end surface of the sliding rod.

3. The steel coil placement rack for an iron trough forming machine according to claim 2, characterized in that: The inclination angle between the linkage push rod and the fixing seat is 60°-70°.

4. The steel coil placement rack for an iron trough forming machine according to claim 1, characterized in that: The end surface of each sliding rod close to the fixed rod is provided with a smooth layer.

5. The steel coil placement rack for an iron trough forming machine according to claim 2, characterized in that: The end surface of each sliding rod close to the fixed rod is provided with an arc surface, and the arc surface is arranged on the smooth layer.

6. The steel coil placement rack for an iron trough forming machine according to claim 4, characterized in that: The smooth layer is a polytetrafluoroethylene layer.

7. The steel coil placement rack for an iron trough forming machine according to claim 1, characterized in that: The end surface of each sliding rod close to the fixed rod is rotatably provided with an abutting roller, which is a nylon roller.

8. A steel coil placement rack for an iron trough forming machine according to claim 1, 2 or 3, characterized in that: An auxiliary sliding groove is provided on the lower end surface of the sliding rod, and at least one arc-shaped placement groove is provided on the fixed seat. Balls are arranged in each arc-shaped placement groove on the fixed seat. The auxiliary sliding groove is provided along the length direction of the sliding rod, and several arc-shaped placement grooves are equidistantly arranged along the length direction of the fixed seat.

9. The steel coil placement rack for an iron trough forming machine according to claim 1, characterized in that: A positioning ring block is provided on the fixing rod in a liftable manner.

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