Multi-stage air cylinder

Abstract

The utility model discloses a multi-stage air cylinder which comprises a second cylinder barrel arranged in a first cylinder barrel in an embedded mode, and a second piston which keeps piston motion with the inner wall of the first cylinder barrel is arranged at the first end of the second cylinder barrel. A first cylinder bottom is fixedly installed at the first end of the first cylinder barrel, a first cylinder cover is fixedly installed at the second end of the first cylinder barrel, and the second cylinder barrel is in sliding fit with the first cylinder cover. A piston rod is nested in the second cylinder barrel, and a third piston which keeps piston movement with the inner wall of the second cylinder barrel is arranged at the first end of the piston rod; and a second cylinder cover is fixedly mounted at the second end of the second cylinder barrel. According to the multi-stage air cylinder, the first cylinder barrel, the second cylinder barrel and the piston rod which are assembled in a nested mode are combined to form an air pipe telescopic mechanism, the second cylinder barrel and the piston rod are driven to synchronously extend through the design of an air channel between the first cylinder barrel and the second cylinder barrel which drive the piston rod to move, and installation space is greatly saved.

Description

Technical Field

[0001] The utility model relates to a cylinder, in particular to a multi-stage cylinder. Background Art

[0002] A cylinder is a cylindrical metal part that guides the piston to perform linear reciprocating motion in the cylinder. It is generally used for linear drive.

[0003] As disclosed in the publication (announcement) number: CN114829786A, the publication (announcement) date: 2022, 07, 29, a cylinder is disclosed, which has a piston rod that can move to a fully extended position, an intermediate position, and a fully retracted position. The cylinder may have a first cylinder head, which engages one end of a first tube and in which a first piston is slidably received; an intermediate connector, which engages the other end of the first tube and one end of a second tube and in which a second piston is slidably received; and a second cylinder head, which engages the other end of the second tube. The piston rod may be attached to the second piston to move therewith, and extend through the intermediate connector, the first piston, the first tube, and the first cylinder head to extend to the outside of the first cylinder head.

[0004] In the prior art including the above patents, single-stage cylinders require a relatively long installation space and cannot be installed in a relatively short space. Therefore, people have developed multi-stage cylinders. However, although the existing double-acting multi-stage cylinders can be installed in a relatively small space, their two inlet and outlet holes are located in the rod side cylinder cover and the rodless side cylinder cover respectively, and the installation of the air pipe in the narrow space will still interfere with external components. Utility Model Content

[0005] The utility model aims to provide a multi-stage cylinder, which solves the problem that two air inlet and outlet holes of the existing multi-stage cylinder cannot be located at the rodless side cylinder cover at the same time.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A multi-stage cylinder comprises a second cylinder barrel nested in a first cylinder barrel, and a second piston is arranged on a first end of the second cylinder barrel to maintain piston motion with an inner wall of the first cylinder barrel;

[0008] A first cylinder bottom is fixedly mounted on the first end of the first cylinder barrel, and a first cylinder cover is fixedly mounted on the second end of the first cylinder barrel, and the second cylinder barrel is slidably matched with the first cylinder cover;

[0009] A piston rod is nested in the second cylinder, and a third piston is arranged on the first end of the piston rod to maintain piston motion with the inner wall of the second cylinder;

[0010] A second cylinder cover is fixedly mounted on the second end of the second cylinder barrel, and the piston rod and the second cylinder cover are in sliding fit;

[0011] The first cylinder bottom is provided with an air inlet and an air outlet.

[0012] Preferably, the second piston is centrally arranged in the first cylinder bottom, and the distance between the two forms a first gap;

[0013] The first gap is in communication with the air outlet and the air outlet.

[0014] Preferably, the third piston and the second piston are spaced apart to form a second gap, and the second piston is provided with air holes arranged in a circumferential array and used to connect the first gap and the second gap.

[0015] Preferably, it also includes a first air pipe inserted through the through hole at the axis center of the first cylinder bottom and fixed by a first fixing block;

[0016] A second air pipe is inserted into the through hole at the axis of the second piston and fixed by a second fixing block, and a sealing pressure ring in contact with the end surface of the second piston is sleeved on the second air pipe;

[0017] The second air pipe is located in a bore opened at one end of the piston rod, and the first air pipe extends into the second air pipe;

[0018] A third fixing block is threadedly mounted on the third piston. The third fixing block is slidably assembled with the second air pipe and contacts the outer wall of the second air pipe through a rubber sealing member provided on its inner wall.

[0019] Preferably, the first air pipe, the second air pipe and the inner hole of the boring hole form a third gap.

[0020] Preferably, a seal is provided between the second air pipe and the first air pipe, and the seal is located at the port of the second air pipe.

[0021] Preferably, the distance between the piston rod and the second cylinder is a fourth gap;

[0022] A second air passage is provided between the piston rod and the third piston to connect the third gap with the fourth gap.

[0023] Preferably, the second cylinder barrel is spaced apart from the first cylinder barrel by a fifth gap;

[0024] A first air passage connecting the third gap and the fifth gap is provided between the second piston and the second air pipe.

[0025] Preferably, the second cylinder head is provided with a sealing member for maintaining a seal between the second cylinder head and the piston rod.

[0026] Preferably, a sealing member is provided on the first cylinder head for maintaining a seal between the first cylinder head and the second cylinder barrel.

[0027] In the above technical scheme, a multi-stage cylinder provided by the utility model has the following beneficial effects: an air pipe telescopic mechanism is formed by a nested first cylinder barrel, a second cylinder barrel and a piston rod combination, and the two air inlets and outlets on the bottom of the first cylinder are used to coordinate and control the air intake and exhaust of the above-mentioned air pipe telescopic mechanism, thereby realizing synchronous driving of the second cylinder barrel and the piston rod in the axial direction to extend and contract, which greatly saves installation space. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0029] Figure 1 An overall cross-sectional view provided for the utility model;

[0030] Figure 2 A schematic diagram of the overall air inlet and outlet positions provided by the utility model;

[0031] Figure 3 A schematic diagram of the gas path when the overall structures provided by the utility model are retracted;

[0032] Figure 4 This is a schematic diagram of the gas path when the overall structures provided by the utility model are extended.

[0033] Description of reference numerals:

[0034] 1. First fixed block; 2. First air pipe; 3. First cylinder bottom; 4. First cylinder barrel; 5. First cylinder head; 21. Second fixed block; 22. Sealing ring; 23. Second piston; 24. Second cylinder barrel; 25. Second air pipe; 26. Second cylinder head; 31. Third fixed block; 32. Third piston; 33. Piston rod; 41. First gap; 42. Air hole; 43. First air duct; 44. Second gap; 45. Second air duct; 46. Third gap; 47. Fourth gap; 48. Fifth gap. DETAILED DESCRIPTION

[0035] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0036] like Figure 1-4As shown, a multi-stage cylinder includes a second cylinder 24 nested in a first cylinder 4, and a second piston 23 is disposed on a first end of the second cylinder 24 to maintain piston motion with the inner wall of the first cylinder 4;

[0037] The first end of the first cylinder barrel 4 is fixedly mounted with the first cylinder bottom 3, and the second end is fixedly mounted with the first cylinder cover 5, and the second cylinder barrel 24 is slidably matched with the first cylinder cover 5;

[0038] A piston rod 33 is nested in the second cylinder 24, and a third piston 32 is provided on the first end of the piston rod 33 to maintain piston motion with the inner wall of the second cylinder 24;

[0039] A second cylinder cover 26 is fixedly mounted on the second end of the second cylinder barrel 24, and the piston rod 33 is slidably fitted with the second cylinder cover 26;

[0040] The first cylinder bottom 3 is provided with an air inlet and an air outlet.

[0041] Specifically, the first cylinder 4, the second cylinder 24 and the piston rod 33 in the embodiment are interconnected, so when an external supply device, such as an air pump, a booster pump or other well-known equipment, injects gas into the first cylinder 4 through the gas outlet, as the internal air pressure of the first cylinder 4 increases, the excess gas enters the second cylinder 24 respectively, and as the air pressure further increases, the second cylinder 24 and the piston rod 33 are extended simultaneously.

[0042] The contraction principle and extension principle of the second cylinder 24 and the piston rod 33 are the same, so no further explanation is given.

[0043] in:

[0044] A sealing member is provided between the second air pipe 25 and the first air pipe 2, and the sealing member is arranged at the port of the second air pipe 25;

[0045] The second cylinder head 26 is provided with a seal for maintaining a seal between the second cylinder head 26 and the piston rod 33;

[0046] The first cylinder head 5 is provided with a sealing member for maintaining a seal between the first cylinder head 5 and the second cylinder barrel 24;

[0047] The sealing member may be a rubber ring, or a rubber sleeve or any other sealing structure known to those skilled in the art.

[0048] In the above technology, the air pipe telescopic mechanism is formed by the nested assembly of the first cylinder 4, the second cylinder 24 and the piston rod 33. The two air inlets and outlets on the first cylinder bottom 3 are used to coordinate and control the air intake and exhaust of the above-mentioned air pipe telescopic mechanism, thereby synchronously driving the second cylinder 24 and the piston rod 33 to extend and contract in the axial direction, greatly saving the installation space.

[0049] As an embodiment further provided by the present invention, the second piston 23 is centrally arranged in the first cylinder bottom 3, and the distance between the two forms a first gap 41; and the first gap 41 is communicated with the air outlet and the air outlet.

[0050] Specific, combined Figure 1 It can be known that in the above embodiment, the gas added from the outside will enter the first gap 41 and push the second piston 23 as the internal gas pressure of the first gap 41 increases.

[0051] As a further optimal embodiment of the present invention, the third piston 32 and the second piston 23 are spaced apart to form a second gap 44 , and the second piston 23 is provided with air holes 42 arranged in a circumferential array and used to connect the first gap 41 and the second gap 44 .

[0052] Specifically, as the internal air pressure of the first gap 41 increases, the gas will enter the second gap 44 through the air hole 42, thereby pushing the third piston 32 to move.

[0053] As another embodiment further provided by the utility model, the embodiment further includes a first air pipe 2 inserted through a through hole at the axis center of the first cylinder bottom 3 and fixed by the first fixing block 1;

[0054] A second air pipe 25 is inserted into the through hole at the axis of the second piston 23 and fixed by the second fixing block 21. The second air pipe 25 is sleeved with a sealing pressure ring 22 in contact with the end surface of the second piston 23.

[0055] The second air pipe 25 is located in a bore formed at one end of the piston rod 33, and the first air pipe 2 extends into the second air pipe 25;

[0056] The third piston 32 is threadedly mounted with a third fixing block 31 , which is slidably assembled with the second air pipe 25 and contacts with the outer wall of the second air pipe 25 via a rubber seal provided on its inner wall.

[0057] Specifically, in the embodiment, the external gas enters from the first air pipe 2 and then expands in the third gap 46, and pushes and drives the third piston 32 to move, that is, to extend. The synchronous third piston 32 follows the movement of the third piston 32, and the space of the third gap 46 increases.

[0058] Because the distance between the piston rod 33 and the second cylinder 24 is the fourth gap 47, and a second air passage 45 is provided between the piston rod 33 and the third piston 32 to connect the third gap 46 and the fourth gap 47. Therefore, when the space of the third gap 46 increases, the space of the fourth gap 47 will decrease.

[0059] Furthermore, the second cylinder 24 and the first cylinder 4 are spaced apart by a fifth gap 48 , and a first air passage 43 is provided between the second piston 23 and the second air pipe 25 to connect the third gap 46 and the fifth gap 48 .

[0060] Therefore, when the space of the third gap 46 increases, the air in the fifth gap 48 will enter the third gap 46 through the first air passage 43, thereby realizing the piston movement of the second piston 23, that is, the second cylinder 24 extends.

[0061] The above only describes some exemplary embodiments of the present invention by way of illustration. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A multi-stage cylinder, characterized in that: It comprises a second cylinder (24) nested in the first cylinder (4), and a second piston (23) is arranged on the first end of the second cylinder (24) to maintain piston motion with the inner wall of the first cylinder (4); A first cylinder bottom (3) is fixedly mounted on a first end of the first cylinder barrel (4), a first cylinder cover (5) is fixedly mounted on a second end, and the second cylinder barrel (24) is slidably matched with the first cylinder cover (5); A piston rod (33) is nested in the second cylinder (24), and a third piston (32) is provided on the first end of the piston rod (33) to maintain piston motion with the inner wall of the second cylinder (24); A second cylinder cover (26) is fixedly mounted on the second end of the second cylinder barrel (24), and the piston rod (33) and the second cylinder cover (26) are in sliding fit; The first cylinder bottom (3) is provided with an air inlet and an air outlet.

2. A multi-stage cylinder according to claim 1, characterized in that: The second piston (23) is centrally arranged in the first cylinder bottom (3), and a first gap (41) is formed between the second piston (23); The first gap (41) is in communication with the air outlet and the air outlet; The third piston (32) and the second piston (23) are spaced apart to form a second gap (44), and the second piston (23) is provided with air holes (42) arranged in a circumferential array and used to connect the first gap (41) and the second gap (44).

3. A multi-stage cylinder according to claim 1, characterized in that: It also includes a first air pipe (2) inserted through a through hole at the axis center of the first cylinder bottom (3) and fixed by a first fixing block (1); A second air pipe (25) is inserted into the through hole at the axis of the second piston (23) and fixed by a second fixing block (21), and a sealing pressure ring (22) is sleeved on the second air pipe (25) and contacts the end surface of the second piston (23); The second air pipe (25) is located in a bore opened at one end of the piston rod (33), and the first air pipe (2) extends into the second air pipe (25); A third fixing block (31) is threadedly mounted on the third piston (32). The third fixing block (31) is slidably assembled with the second air pipe (25) and contacts the outer wall of the second air pipe (25) through a rubber seal provided on its inner wall.

4. A multi-stage cylinder according to claim 3, characterized in that: The first air pipe (2), the second air pipe (25) and the inner hole of the boring hole form a third gap (46).

5. A multi-stage cylinder according to claim 3, characterized in that: A sealing member is provided between the second air pipe (25) and the first air pipe (2), and the sealing member is arranged at the port of the second air pipe (25).

6. A multi-stage cylinder according to claim 1, characterized in that: The distance between the piston rod (33) and the second cylinder barrel (24) is a fourth gap (47); A second air passage (45) is provided between the piston rod (33) and the third piston (32) to connect the third gap (46) and the fourth gap (47).

7. A multi-stage cylinder according to claim 1, characterized in that: The second cylinder (24) and the first cylinder (4) are spaced apart by a fifth gap (48); A first air passage (43) is provided between the second piston (23) and the second air pipe (25) to connect the third gap (46) and the fifth gap (48).

8. A multi-stage cylinder according to claim 1, characterized in that: The second cylinder head (26) is provided with a sealing member for maintaining a seal between the second cylinder head (26) and the piston rod (33).

9. A multi-stage cylinder according to claim 1, characterized in that: The first cylinder head (5) is provided with a sealing member for maintaining a seal between the first cylinder head (5) and the second cylinder barrel (24).

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