A multi-station drilling machine

Abstract

The present invention discloses a multi-station drilling machine, comprising an electric hydraulic lifting rod, a fixed block is fixedly connected to the top of the electric hydraulic lifting rod, a connecting block is fixedly connected to the outer wall of the connecting block, a sliding rod is fixedly connected to the outer wall of the sliding rod, an electric sliding block is slidably connected to the outer wall of the sliding rod, an electric hydraulic lifting rod is arranged inside the electric sliding block, a drill bit is arranged inside the electric hydraulic lifting rod, and an iron chip adsorption and anti-splashing mechanism is arranged outside the electric hydraulic lifting rod, which relates to the technical field of drilling machines. By arranging the iron chip adsorption and anti-splashing mechanism, the sliding scraper of the outer wall of the arc-shaped magnetic plate at the spherical position is pulled back again by the elastic force of the elastic rope, so that as the drilling hole continues to go deeper, the iron chips adhered to the outer wall of the arc-shaped magnetic plate are slowly scraped, and the iron chips are concentratedly collected near the rotating shaft to ensure the cleanliness of the outer wall of the arc-shaped magnetic plate, and further improve the subsequent collection and adsorption efficiency of the arc-shaped magnetic plate on the iron chips.

Description

Technical Field

[0001] The invention relates to the technical field of drilling machines, in particular to a multi-station drilling machine. Background Art

[0002] A drilling machine refers to a machine tool that mainly uses a drill to make holes on a workpiece. Usually, the rotation of the drill bit is the main motion, and the axial movement of the drill bit is the feed motion. The drilling machine has a simple structure and relatively low processing accuracy. It can drill through holes and blind holes. By replacing special tools, it can expand, countersink, ream holes, or perform tapping and other processing. During the processing, the workpiece does not move, and the tool moves, aligning the center of the tool with the center of the hole, and rotating the tool (main motion). The characteristics of a drilling machine are that the workpiece is fixed and the tool rotates;

[0003] In the current multi-station drilling machine, a large amount of metal chips are generated when the drilling machine is working, which fly everywhere. A large amount of chips are wasted and pollute the surrounding air and environment. Subsequent cleaning by the staff requires a lot of time and energy, and it is impossible to maximize the collection of chips. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a multi-station drilling machine to achieve the purpose of solving the above-mentioned problems.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a multi-station drilling machine, comprising a base, a fixed block is fixedly connected to the top of the base, a connecting block is fixedly connected to the outer wall of the connecting block, an electric slider is slidably connected to the outer wall of the sliding rod, an electric hydraulic lifting rod is arranged inside the electric slider, a drill bit is arranged inside the electric hydraulic lifting rod, and an iron chip adsorption and anti-splashing mechanism is arranged outside the electric hydraulic lifting rod;

[0006] The iron-chip adsorption and anti-splashing mechanism comprises an arc-shaped magnetic plate, one end of which is fixedly connected to a rotating shaft, the outer wall of the rotating shaft is slidably connected to the outer wall of the electric hydraulic lifting rod through a sliding groove, the outer wall of the arc-shaped magnetic plate is fixedly connected to an elastic strip, one end of the arc-shaped magnetic plate is fixedly connected to a round ball, the outer wall of the arc-shaped magnetic plate is slidably connected to a sliding scraper, the outer wall of the sliding scraper is fixedly connected to an elastic rope, one end of the elastic rope is fixedly connected to the outer wall of the rotating shaft, the outer wall of the sliding scraper is provided with an arc-shaped groove, and an iron-chip collecting and cleaning mechanism is arranged outside the sliding scraper;

[0007] The iron filings collection and cleaning mechanism includes an opening and closing scraper, the outer wall of the opening and closing scraper is fixedly connected to a small elastic rope, one end of the small elastic rope is fixedly connected to the outer wall of the arc-shaped magnetic plate, the inner wall of the opening and closing scraper is rotatably connected to a rotating shaft through a bearing, the outer wall of the rotating shaft is fixedly connected to the outer wall of the arc-shaped magnetic plate, the outer wall of the sliding scraper is slidably connected to a long scraper through a sliding groove, and the outer wall of the sliding scraper is fixedly connected to a block A and a block B.

[0008] Preferably, the block B is magnetic and the arc-shaped magnetic plate is magnetic.

[0009] Preferably, the gravity of the sliding scraper in a vertical state is greater than the elastic force of the elastic rope.

[0010] Preferably, the inner wall of the arc-shaped groove is arc-shaped.

[0011] Preferably, the outer wall of the sphere is spherical.

[0012] Preferably, the outer wall of the arc-shaped magnetic plate is arc-shaped.

[0013] Preferably, the elastic force of the small elastic rope is smaller than the elastic force of the elastic rope.

[0014] The present invention provides a multi-station drilling machine. It has the following beneficial effects:

[0015] (1) The present invention provides an iron chip adsorption and splash prevention mechanism. After the sliding scraper slides to the sphere, the drill bit starts to rotate through the motor drive inside the electric hydraulic lifting rod to punch the workpiece. When punching, a large amount of iron chips are randomly adsorbed and adhered to the outer wall of the arc-shaped magnetic plate, thereby realizing the collection of iron chips. As the electric hydraulic lifting rod continuously pushes the drill bit to drill down, the sphere at the bottom of the arc-shaped magnetic plate touches the fixed block or the workpiece surface, thereby being resisted. As the electric hydraulic lifting rod descends, the sphere at the bottom of the arc-shaped magnetic plate passes through the arc of the outer wall. The surface slides to both sides on the surface of the fixed block, driving the arc-shaped magnetic plate and the rotating shaft to rotate, realizing the opening and closing of the arc-shaped magnetic plate, so that the arc-shaped magnetic plate is opened, and the gradually opened arc-shaped magnetic plate is gradually flattened from a vertical state, so that the sliding scraper on the outer wall of the arc-shaped magnetic plate at the spherical position is pulled back again by the elastic force of the elastic rope, so that as the drilling hole continues to go deeper, the iron filings adhered to the outer wall of the arc-shaped magnetic plate are slowly scraped away, and the iron filings are concentrated and collected near the rotating shaft, ensuring the cleanliness of the outer wall of the arc-shaped magnetic plate, and further improving the subsequent arc-shaped magnetic plate The efficiency of collecting and adsorbing iron filings is further improved.

[0016] (2) The present invention provides an iron chip adsorption and splash prevention mechanism. When the drill bit is driven down by the electric hydraulic lifting rod to drill a hole in a workpiece, as the electric hydraulic lifting rod descends, the rotating shaft and the arc-shaped magnetic plate descend synchronously. The arc-shaped magnetic plate is limited by the elastic strip and remains stationary. When the arc-shaped magnetic plate gradually approaches the metal workpiece and the fixed block, the arc-shaped magnetic plate attracts the iron through its own magnetism, so that the arc-shaped magnetic plate drives the rotating shaft to rotate on the outer wall of the electric hydraulic lifting rod, and the sphere at one end of the arc-shaped magnetic plate approaches the workpiece and the fixed block, so that the arc-shaped magnetic plate rotates gradually vertically, so that the sliding scraper on the outer wall of the arc-shaped magnetic plate gradually becomes vertical on the outer wall of the arc-shaped magnetic plate, and the downward gravity of the sliding scraper gradually increases, thereby pulling the elastic rope to stretch and deform, and the sliding scraper slides on the outer wall of the arc-shaped magnetic plate to the sphere and is blocked by the sphere, thereby scraping off the iron chips and dust adhered to the outer wall of the arc-shaped magnetic plate, ensuring the cleanliness of the outer wall of the arc-shaped magnetic plate and improving the effect of the arc-shaped magnetic plate on the magnetic attraction of iron chips.

[0017] (3) The present invention provides an iron chip adsorption and splash prevention mechanism. After punching is completed, the electric hydraulic lifting rod is quickly lifted, driving the drill bit to rise synchronously. The arc-shaped magnetic plate with the outer wall opened is no longer supported by the fixed block, and is quickly pushed back to its original position by the elastic force of the elastic strip, thereby realizing rapid resetting of the arc-shaped magnetic plate. The arc-shaped magnetic plate vibrates under the elastic force of the elastic strip to clean the outer wall of the arc-shaped magnetic plate, and the dust and residue outside the iron chips adhered to the outer wall of the arc-shaped magnetic plate are opened and closed to shake off, thereby avoiding affecting the purity and efficiency of the iron chips collected by the arc-shaped magnetic plate.

[0018] (4) The present invention provides an iron filings collection and cleaning mechanism, and the sliding scraper is thrown out by the centrifugal force of the arc-shaped magnetic plate as the arc-shaped magnetic plate rotates rapidly, and the sliding scraper slides toward the sphere on the outer wall of the arc-shaped magnetic plate and pulls the elastic rope to deform. After the arc-shaped magnetic plate stops rotating, the sliding scraper is pulled back to its original position by the elastic rope. When the sliding scraper slides to its original position, the outer wall of the elastic rope contacts the tip of the opening and closing scraper and pushes the opening and closing scraper to rotate on the outer wall. As the opening and closing scraper rotates, the small elastic rope is pulled to stretch and deform, and the opening and closing scraper The plate contacts both sides of the inner wall of the arc-shaped groove opened on the outer wall of the sliding scraper, and slides to the middle of the inner wall of the arc-shaped groove as the opening and closing scraper rotates, so as to scrape a large amount of iron filings pushed by the sliding scraper through the arc-shaped groove and collect them between the two opening and closing scrapers, and separate the iron filings in the arc-shaped groove, so as to realize automatic collection of the iron filings in the arc-shaped groove of the outer wall of the sliding scraper, and avoid the situation that when the punching work is performed again, the sliding scraper slides down and brings the iron filings inside the arc-shaped groove back to the outer wall of the arc-shaped magnetic plate due to adhesion.

[0019] (5) The present invention sets an iron filings collection and cleaning mechanism. When the arc-shaped magnetic plate rotates rapidly, the long scraper on the outer wall of the sliding scraper is driven by the centrifugal force of the arc-shaped magnetic plate to slide synchronously on the outer wall of the sliding scraper. After the long scraper slides out of the magnetic attraction of the block B, when the arc-shaped magnetic plate stops rotating, the long scraper is again attracted back by the magnetic attraction of the block B, thereby scraping off the iron filings and non-iron filings dust adhered to the surface of the sliding scraper, avoiding the situation where a large amount of iron filings adhere to the outer wall of the sliding scraper and a large amount of non-iron filings are wrapped in the iron filings, which results in impure iron filings and excessive residues when the iron filings are subsequently recovered. The outer wall of the sliding scraper is further cleaned, which improves the iron filings collection effect and ensures the magnetic attraction of the arc-shaped magnetic plate to the iron filings next time. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of the present invention;

[0021] Figure 2 It is a structural schematic diagram of the electric hydraulic lifting rod of the present invention;

[0022] Figure 3 It is a structural schematic diagram of the iron chips adsorption and splash prevention mechanism of the present invention;

[0023] Figure 4 It is a structural schematic diagram of the iron filings collecting and cleaning mechanism of the present invention;

[0024] Figure 5 It is a structural schematic diagram of the long scraper of the present invention;

[0025] Figure 6 It is a structural schematic diagram of the opening and closing scraper of the present invention.

[0026] In the figure: 1 connecting block, 2 electric hydraulic lifting rod, 3 iron chip adsorption and anti-splashing mechanism, 301 arc magnetic plate, 302 rotating shaft, 303 elastic strip, 304 sliding scraper, 305 ball, 306 elastic rope, 307 arc groove, 4 iron chip collection and cleaning mechanism, 401 opening and closing scraper, 402 small elastic rope, 403 long scraper, 404 block A, 405 block B, 406 rotating shaft, 5 fixed block, 6 drill bit, 7 electric slider, 8 slide rod, 9 base. DETAILED DESCRIPTION

[0027] See also Figure 1-6 The present invention provides a technical solution: a multi-station drilling machine, comprising a base 9, a fixed block 5 is fixedly connected to the top of the base 9, a connecting block 1 is fixedly connected to the top of the base 9, a sliding rod 8 is fixedly connected to the outer wall of the connecting block 1, an electric sliding block 7 is slidably connected to the outer wall of the sliding rod 8, an electric hydraulic lifting rod 2 is arranged inside the electric sliding block 7, a drill bit 6 is arranged inside the electric hydraulic lifting rod 2, and an iron chip adsorption and anti-splashing mechanism 3 is arranged outside the electric hydraulic lifting rod 2;

[0028] The iron-chip adsorption and splash-proof mechanism 3 comprises an arc-shaped magnetic plate 301, the outer wall of the arc-shaped magnetic plate 301 is in an arc shape, one end of the arc-shaped magnetic plate 301 is fixedly connected with a rotating shaft 302, the outer wall of the rotating shaft 302 is slidably connected with the outer wall of the electric hydraulic lifting rod 2 through a slide groove, the outer wall of the arc-shaped magnetic plate 301 is fixedly connected with an elastic strip 303, one end of the arc-shaped magnetic plate 301 is fixedly connected with a sphere 305, the outer wall of the sphere 305 is in a spherical shape, the outer wall of the arc-shaped magnetic plate 301 is slidably connected with a sliding scraper 304, the gravity of the sliding scraper 304 in a vertical state is greater than the elastic force of the elastic rope 306, the outer wall of the sliding scraper 304 is fixedly connected with an elastic rope 306, one end of the elastic rope 306 is fixedly connected with the outer wall of the rotating shaft 302, the outer wall of the sliding scraper 304 is provided with an arc-shaped groove 307, the inner wall of the arc-shaped groove 307 is in an arc shape, and an iron-chip collecting and cleaning mechanism 4 is arranged outside the sliding scraper 304;

[0029] The iron filings collecting and cleaning mechanism 4 includes an opening and closing scraper 401, and a small elastic rope 402 is fixedly connected to the outer wall of the opening and closing scraper 401. The elastic force of the small elastic rope 402 is less than the elastic force of the elastic rope 306. One end of the small elastic rope 402 is fixedly connected to the outer wall of the arc-shaped magnetic plate 301. The inner wall of the opening and closing scraper 401 is rotatably connected to a rotating shaft 406 through a bearing. The outer wall of the rotating shaft 406 is fixedly connected to the outer wall of the arc-shaped magnetic plate 301. The outer wall of the sliding scraper 304 is slidably connected to a long scraper 403 through a slide groove. The outer wall of the sliding scraper 304 is fixedly connected to a block A404 and a block B405. The block B405 is magnetic, and the arc-shaped magnetic plate 301 is magnetic.

[0030] When in use, by adjusting the position of the electric slider 7 on the slide bar 8 on one side of the connecting block 1, the drill bit 6 at the bottom of the electric hydraulic lifting rod 2 is driven to the specified position, and then the electric hydraulic lifting rod 2 is started to lift and lower on the inner wall of the electric slider 7 to drill the workpiece placed on the fixed block 5. When drilling, a large amount of drilling waste chips are scattered and attracted to the outer wall of the arc-shaped magnetic plate 301 by the magnetism of the arc-shaped magnetic plate 301, so that they are automatically adsorbed on the arc-shaped magnetic plate 301, avoiding the problem of difficulty in cleaning caused by the splashing of iron chips.

[0031] When the drill bit 6 is driven down by the electric hydraulic lifting rod 2 to drill a hole in the workpiece, as the electric hydraulic lifting rod 2 descends, the rotating shaft 302 and the arc-shaped magnetic plate 301 descend synchronously, and the arc-shaped magnetic plate 301 is limited by the elastic strip 303 and remains stationary. When the arc-shaped magnetic plate 301 gradually approaches the metal workpiece and the fixed block 5, the arc-shaped magnetic plate 301 is magnetically attracted to iron through its own magnetism, so that the arc-shaped magnetic plate 301 drives the rotating shaft 302 to rotate on the outer wall of the electric hydraulic lifting rod 2, and the ball 305 at one end of the arc-shaped magnetic plate 301 approaches the workpiece and the fixed block 5. , so that the arc-shaped magnetic plate 301 rotates and gradually becomes vertical, so that the sliding scraper 304 on the outer wall of the arc-shaped magnetic plate 301 gradually becomes vertical on the outer wall of the arc-shaped magnetic plate 301, and the downward gravity of the sliding scraper 304 gradually increases, thereby pulling the elastic rope 306 to stretch and deform, and the sliding scraper 304 slides on the outer wall of the arc-shaped magnetic plate 301 to the ball 305, and is blocked by the ball 305, so that the iron filings and dust adhered to the outer wall of the arc-shaped magnetic plate 301 are scraped off, ensuring the cleanliness of the outer wall of the arc-shaped magnetic plate 301, and improving the magnetic attraction effect of the arc-shaped magnetic plate 301 on iron filings;

[0032] After the sliding scraper 304 slides to the ball 305, the drill bit 6 starts to rotate through the motor drive inside the electric hydraulic lifting rod 2 to punch the workpiece. When punching, a large amount of iron filings are randomly adsorbed and adhered to the outer wall of the arc-shaped magnetic plate 301, thereby realizing the collection of iron filings. As the electric hydraulic lifting rod 2 continuously pushes the drill bit 6 to drill and descend, the ball 305 at the bottom of the arc-shaped magnetic plate 301 touches the fixed block 5 or the surface of the workpiece, and is thus resisted. As the electric hydraulic lifting rod 2 descends, the ball 305 at the bottom of the arc-shaped magnetic plate 301 slides to both sides on the surface of the fixed block 5 through the arc surface of the outer wall. The arc-shaped magnetic plate 301 and the rotating shaft 302 are driven to rotate, so as to realize the opening and closing of the arc-shaped magnetic plate 301, so that the arc-shaped magnetic plate 301 is opened, and the gradually opened arc-shaped magnetic plate 301 is gradually flattened from a vertical state, so that the sliding scraper 304 of the outer wall of the arc-shaped magnetic plate 301 at the position of the ball 305 is pulled back again by the elastic force of the elastic rope 306, so as to realize that as the drilling hole continues to go deeper, the iron filings adhered to the outer wall of the arc-shaped magnetic plate 301 are slowly scraped away, and the iron filings are concentrated and collected near the rotating shaft 302, so as to ensure the cleanliness of the outer wall of the arc-shaped magnetic plate 301, and further improve the subsequent collection and adsorption efficiency of the iron filings by the arc-shaped magnetic plate 301;

[0033] After the punching is completed, the electric hydraulic lifting rod 2 is quickly lifted, driving the drill bit 6 to rise synchronously, and the arc-shaped magnetic plate 301 with the outer wall opened is no longer held by the fixed block 5, and is quickly pushed back to its original position by the elastic force of the elastic strip 303, so as to realize the rapid reset of the arc-shaped magnetic plate 301. The arc-shaped magnetic plate 301 is vibrated once under the elastic force of the elastic strip 303, so as to realize the cleaning of the outer wall of the arc-shaped magnetic plate 301, and the dust and residue outside the iron filings adhered to the outer wall of the arc-shaped magnetic plate 301 are opened and closed to shake off, so as to avoid affecting the purity and efficiency of the iron filings collected by the arc-shaped magnetic plate 301;

[0034] As the arc-shaped magnetic plate 301 rotates rapidly, the sliding scraper 304 is thrown out by the centrifugal force of the arc-shaped magnetic plate 301, and the sliding scraper 304 slides on the outer wall of the arc-shaped magnetic plate 301 toward the sphere 305, and pulls the elastic rope 306 to deform. As the arc-shaped magnetic plate 301 stops rotating, the sliding scraper 304 is pulled back to its original position by the elastic rope 306 again. When the sliding scraper 304 slides to its original position, the outer wall of the elastic rope 306 contacts the tip of the opening and closing scraper 401 and pushes the opening and closing scraper 401 to rotate on the outer wall of the rotating shaft 406. As the opening and closing scraper 401 rotates, the small elastic rope 402 is pulled to stretch and deform, and the opening and closing scraper 401 moves The scraper 401 contacts the two sides of the inner wall of the arc groove 307 formed on the outer wall of the sliding scraper 304, and slides to the middle of the inner wall of the arc groove 307 as the opening and closing scraper 401 rotates, so as to scrape a large amount of iron filings pushed by the sliding scraper 304 through the arc groove 307 and collect them between the two opening and closing scrapers 401, so as to separate the iron filings in the arc groove 307, and realize automatic collection of the iron filings in the arc groove 307 on the outer wall of the sliding scraper 304, thereby avoiding the situation that when punching is performed again, the sliding scraper 304 slides down and brings the iron filings inside the arc groove 307 back to the outer wall of the arc magnetic plate 301 again due to adhesion;

[0035] And when the arc-shaped magnetic plate 301 rotates rapidly, the long scraper 403 on the outer wall of the sliding scraper 304 is driven by the centrifugal force selected by the arc-shaped magnetic plate 301 to slide synchronously on the outer wall of the sliding scraper 304. After the long scraper 403 slides out of the magnetic attraction of the block B405, when the arc-shaped magnetic plate 301 stops rotating, the long scraper 403 is again attracted back by the magnetic attraction of the block B405, thereby scraping off the iron filings and non-iron filings dust adhered to the surface of the sliding scraper 304, avoiding the situation where a large amount of iron filings adhere to the outer wall of the sliding scraper 304 and a large amount of non-iron filings are wrapped in the iron filings, which leads to impure iron filings and excessive residues when the iron filings are subsequently recovered. The outer wall of the sliding scraper 304 is further cleaned, which improves the iron filing collection effect while ensuring the magnetic attraction strength of the arc-shaped magnetic plate 301 to the iron filings next time.

[0036] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A multi-station drilling machine, comprising a base (9), characterized in that: The top of the base (9) is fixedly connected to a fixed block (5), the top of the base (9) is fixedly connected to a connecting block (1), the outer wall of the connecting block (1) is fixedly connected to a sliding rod (8), the outer wall of the sliding rod (8) is slidably connected to an electric slider (7), an electric hydraulic lifting rod (2) is arranged inside the electric slider (7), a drill bit (6) is arranged inside the electric hydraulic lifting rod (2), and an iron filings adsorption and splash prevention mechanism (3) is arranged outside the electric hydraulic lifting rod (2); The iron-chip adsorption and splash-proof mechanism (3) comprises an arc-shaped magnetic plate (301), one end of the arc-shaped magnetic plate (301) is fixedly connected to a rotating shaft (302), the outer wall of the rotating shaft (302) is slidably connected to the outer wall of the electric hydraulic lifting rod (2) through a sliding groove, the outer wall of the arc-shaped magnetic plate (301) is fixedly connected to an elastic strip (303), one end of the arc-shaped magnetic plate (301) is fixedly connected to a round ball (305), the outer wall of the arc-shaped magnetic plate (301) is slidably connected to a sliding scraper (304), the outer wall of the sliding scraper (304) is fixedly connected to an elastic rope (306), one end of the elastic rope (306) is fixedly connected to the outer wall of the rotating shaft (302), the outer wall of the sliding scraper (304) is provided with an arc-shaped groove (307), and an iron-chip collecting and cleaning mechanism (4) is arranged outside the sliding scraper (304); The scrap iron collection and cleaning mechanism (4) comprises an opening and closing scraper (401), the outer wall of the opening and closing scraper (401) is fixedly connected to a small elastic rope (402), one end of the small elastic rope (402) is fixedly connected to the outer wall of the arc-shaped magnetic plate (301), the inner wall of the opening and closing scraper (401) is rotatably connected to a rotating shaft (406) via a bearing, the outer wall of the rotating shaft (406) is fixedly connected to the outer wall of the arc-shaped magnetic plate (301), the outer wall of the sliding scraper (304) is slidably connected to a long scraper (403) via a sliding groove, and the outer wall of the sliding scraper (304) is fixedly connected to a stopper A (404) and a stopper B (405).

2. A multi-station drilling machine according to claim 1, characterized in that: The stopper B (405) is magnetic, and the arc-shaped magnetic plate (301) is magnetic.

3. A multi-station drilling machine according to claim 2, characterized in that: The gravity of the sliding scraper (304) in a vertical state is greater than the elastic force of the elastic rope (306).

4. The multi-station drilling machine according to claim 3, characterized in that: The inner wall of the arc-shaped groove (307) is in an arc shape.

5. The multi-station drilling machine according to claim 4, characterized in that: The outer wall of the sphere (305) is spherical.

6. The multi-station drilling machine according to claim 5, characterized in that: The outer wall of the arc-shaped magnetic plate (301) is in an arc shape.

7. The multi-station drilling machine according to claim 6, characterized in that: The elastic force of the small elastic string (402) is smaller than the elastic force of the elastic string (306).

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