Double-rod type large-cylinder-diameter air cylinder

Abstract

A double-rod type large-cylinder-diameter air cylinder comprises a cylinder body and a piston, the two ends of a cavity of the cylinder body are connected with a front end cover and a rear end cover in a sealed mode respectively, the outer circumferential face of the piston is attached to the inner wall of the cavity in a sliding mode, the two ends of the piston are both connected with piston rods, and the front end cover and the rear end cover are both provided with through holes allowing the corresponding piston rods to penetrate through. A first sealing piece in sealing contact with the peripheral face of the corresponding piston rod is further arranged in the through hole, a limiting piece in limiting fit with the rear end cover is further arranged at the outer end of the piston rod located at the lower end, and the limiting piece can move in the length direction of the corresponding piston rod so that the distance between the limiting piece and the rear end cover can be adjusted. By arranging the double piston rods and moving the limiting piece on the piston rod at the lower end, the stroke of the piston rod at the lower end is adjusted, so that the purpose of adjusting the stroke of the piston rod at the upper end is achieved, the operation is convenient, the structure is simple, the design is reasonable, and the practicability is also high.

Description

Technical Field

[0001] The utility model relates to the technical field of large-diameter cylinders, in particular to a double-rod large-diameter cylinder. Background Art

[0002] A large-diameter cylinder can be used as a jig cylinder, and the extension and retraction of the piston rod is used to clamp or loosen the workpiece by the jig, thereby improving the efficiency of automated work. The existing large-diameter cylinders all adopt a single-rod structure in their structural design. The cylinder with this structure cannot adjust the stroke of the piston rod. When processing the same workpiece of different heights, it is necessary to replace jigs of different sizes to clamp them. The structure is unreasonable and the operation is inconvenient. Utility Model Content

[0003] In view of the shortcomings of the above-mentioned prior art, the purpose of the utility model is to provide a double-rod large-bore cylinder which can adjust the stroke of the piston rod and has higher practicality.

[0004] The utility model adopts a technical solution to solve its technical problems. A double-rod large-bore cylinder comprises a cylinder body and a piston. The cylinder body is provided with a cavity with two ends passing through. The two ends of the cavity are respectively sealed and connected with a front end cover and a rear end cover. The cylinder body is provided with a first air hole at a position below the front end cover, and the cylinder body is provided with a second air hole at an upper position relative to the rear end cover. The first air hole and the second air hole are both connected with the cavity. The outer peripheral surface of the piston can be slidably fitted on the inner wall of the cavity. The two ends of the piston are connected with piston rods. The front end cover and the rear end cover are both provided with through holes for the corresponding piston rods to pass through. The through holes are also provided with first sealing members that form a sealing contact with the outer peripheral surface of the corresponding piston rod. The outer end of the piston rod located at the lower end is also provided with a limiting member that cooperates with the rear end cover. The limiting member can move along the length direction of the corresponding piston rod so that the spacing between it and the rear end cover is adjustable.

[0005] Furthermore, the interior of the limit member is provided with an internal thread section and a non-thread section at the upper and lower parts, the inner diameter of the internal thread section is smaller than the inner diameter of the non-thread section, and the corresponding outer end top of the piston rod is set as a small-diameter external thread section, the external thread section is threadedly connected to the internal thread section, and the inner diameter of the non-thread section is adapted to the diameter of the corresponding smooth section of the piston rod.

[0006] Furthermore, the inner surfaces of the front cover and the rear cover are each provided with a first annular cavity, the through holes are each formed at the center of the corresponding first annular cavity, and the first annular cavity is each provided with a second sealing member that forms a sealing contact with the corresponding outer peripheral surface of the piston rod.

[0007] Furthermore, a second annular cavity is correspondingly provided between the inner surfaces of the front end cover and the rear end cover and the opposite surface of the piston. The second annular cavity is arranged relative to the outer side of the first annular cavity, and the second annular cavity is used for installing a flexible buffer.

[0008] Furthermore, at least one first annular groove and at least one second annular groove are provided on the outer circumferential surface of the piston, the first annular groove is used to install the third sealing member, and the second annular groove is located below the first annular groove and is used to install the supporting ring.

[0009] Furthermore, the upper and lower surfaces of the piston are provided with axial holes corresponding to the through hole, the bottom center of the axial hole is provided with a hollow hole that penetrates and connects, and the end of the piston rod that cooperates with the axial hole is provided with a third annular groove, and the third annular groove is used to install a fourth seal.

[0010] Furthermore, the outer circumferential surfaces of the front end cover and the rear end cover are each provided with a fourth annular groove and an annular limiting boss located outside the fourth annular groove, the fourth annular groove is used to install a fifth seal, and annular limiting recesses matching the annular limiting bosses are provided at the upper and lower ends of the cavity, and a fifth annular groove is provided at the root of the annular limiting recess, and the fifth annular groove is used to place a retaining ring.

[0011] The beneficial effects of the utility model are:

[0012] (1) During the operation of the utility model, the piston drives the piston rods at the upper and lower ends to move. When the piston rod at the lower end moves upward for a certain distance, the limit piece on it forms a contact limit with the rear end cover, thereby limiting the upward movement of the piston, and the limit piece and the piston rod at the lower end are matched through a threaded connection structure. Therefore, the limit piece can move along the length direction of the piston rod at the lower end, so that the distance between the limit piece and the rear end cover can be adjusted, thereby achieving the purpose of adjusting the stroke of the upper piston rod, and the adjustment is convenient and more practical. At the same time, a non-threaded section with a larger inner diameter is provided below the internal threaded section of the limit piece, and the smooth section on the piston rod at the lower end is adapted to the non-threaded section. Under the premise of ensuring stable limit, this arrangement ensures that the limit piece and the rear end cover are repeatedly contacted and limited, and the collision force generated by the two will not cause damage to the threaded structure, thereby ensuring the service life.

[0013] (2) The utility model provides a first seal member in the through hole of the front cover and the rear cover to form a sealing contact with the outer peripheral surface of the corresponding piston rod, provides a first annular cavity on the inner surface of the front cover and the rear cover, and provides a second seal member in the first annular cavity to form a sealing contact with the outer peripheral surface of the corresponding plug rod, provides a fourth annular groove on the outer peripheral surface of the front cover and the rear cover, and installs a fifth seal member in the fourth annular groove to form a sealing contact with the wall surface of the cavity. Through the above structure, the gas in the cavity will not leak from the connection between the front cover, the rear cover and the cylinder body and the matching point between the piston rod and the through hole; at least one first annular groove is provided on the outer peripheral surface of the piston, and a third seal member is provided in the first annular groove, so that the piston divides the cavity into two closed chambers, and axial holes corresponding to the through holes are provided on the two side surfaces of the piston, the axial holes realize the effective fixation of the piston, and the bottom center of the axial hole is penetrated to form a hollow hole, and the fourth seal member is provided in the third annular groove on the end of the piston rod that matches in the axial hole, so that the purpose of reducing the weight of the piston is achieved and the sealing effect is also guaranteed, and the overall sealing effect is good.

[0014] (3) The utility model provides a second annular cavity correspondingly between the inner surfaces of the front end cover and the rear end cover and the relative surface of the piston, and installs a flexible buffer in the second annular cavity. The flexible buffer can provide buffering protection for the piston, the front end cover and the rear end cover, and also reduce the noise generated during movement. At least one second annular groove is provided on the outer circumferential surface of the piston, and a supporting ring is installed in the second annular groove. The supporting ring can realize the function of supporting the piston to prevent axial deviation, thereby further reducing the noise generated during movement. The overall structural design is reasonable. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0016] Figure 2 This is a partial structural section of the utility model Figure 1 ;

[0017] Figure 3 This is a cross-sectional view of the limiter structure of the utility model;

[0018] Figure 4 This is a partial structural section of the utility model Figure 2 ;

[0019] Figure 5 This is a cross-sectional view of the cylinder structure of the utility model;

[0020] Figure 6 This is a cross-sectional view of the piston structure of the utility model.

[0021] In the figure: 1-cylinder body, 2-piston, 3-cavity, 4-front end cover, 5-rear end cover, 6-first air hole, 7-second air hole, 8-piston rod, 9-through hole, 10-first sealing member, 11-limiting member, 12-inner thread section, 13-unthreaded section, 14-external thread section, 15-first annular cavity, 16-second sealing member, 17-second annular cavity, 18-flexible buffer member, 19-first annular groove, 20-second annular groove, 21-third sealing member, 22-supporting ring member, 23-axial hole, 24-hollow hole, 25-third annular groove, 26-fourth sealing member, 27-fourth annular groove, 28-annular limiting boss, 29-fifth sealing member, 30-annular limiting recess, 31-fifth annular groove, 32-circlip, 33-sixth annular groove. DETAILED DESCRIPTION

[0022] In order to more clearly illustrate the embodiments of the utility model and / or the technical solutions in the prior art, the specific implementation methods of the utility model will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work. In addition, the orientation only represents the relative position relationship between the components, not the absolute position relationship.

[0023] See also Figures 1 to 6 As shown, a double-rod large-bore cylinder comprises a cylinder body 1 and a piston 2. The cylinder body 1 is provided with a cavity 3 with two ends through it. The two ends of the cavity 3 are respectively sealed and connected with a front cover 4 and a rear cover 5. A first air hole 6 is provided on the cylinder body 1 at a lower position relative to the front cover 4, and a second air hole 7 is provided on the cylinder body 1 at an upper position relative to the rear cover 5. The first air hole 6 and the second air hole 7 are both connected to the cavity 3. The first air hole 6 and the second air hole 7 are used for air intake or exhaust. The outer peripheral surface of the piston 2 can be slidably attached to the inner wall of the cavity 3. The plug 2 divides the cavity 3 into two parts. Piston rods 8 are connected to both ends of the piston 2. Through holes 9 are provided on the front cover 4 and the rear cover 5 for the corresponding piston rods 8 to pass through. A first sealing member 10 is also provided in the through hole 9 to form a sealing contact with the outer peripheral surface of the corresponding piston rod 8. With this arrangement, when the piston rods 8 at both ends extend or retract, the gas in the cavity 3 will not leak from the connection between the cavity 3 and the front cover 4 and the rear cover 5, and the matching position between the through hole 9 and the piston rod 8, thereby ensuring the sealing effect and the high movement stability of the piston rod 8.

[0024] In this embodiment, a stopper 11 which cooperates with the rear end cover 5 is further provided on the outer end of the piston rod 8 at the lower end. The stopper 11 can move along the length direction of the corresponding piston rod 8 so that the spacing between it and the rear end cover 5 can be adjusted. More specifically, when the piston 2 moves up and down along the inner wall of the cavity 3, if the piston rod 8 at the upper end extends out of the cylinder body 1 from the through hole 9 on the front end cover 4, the piston rod 8 at the lower end will move into the cylinder body 1 through the through hole on the rear end cover 5. When the piston 2 contacts the inner surface of the front end cover 4 or the rear end cover 5, the piston rod 8 will reach the maximum displacement. The limit piece 11 is combined, and the limit piece 11 can move along the length direction of the corresponding piston rod 8. When the stroke of the upper piston rod 8 needs to be adjusted, it is only necessary to move the limit piece 11 toward the rear end cover 5, so that the distance between the limit piece 11 and the rear end cover 5 is smaller than the distance between the upper surface of the piston 2 and the front end cover 4 (when the lower surface of the piston 2 contacts the rear end cover 5). The displacement of the upper piston rod 8 from the through hole 9 on the front end cover 4 to the outside of the cylinder body 1 will be smaller than the maximum displacement, so that the fixture installed on the upper end of the piston rod 8 can achieve clamping of the same workpiece at different heights, and it is more practical and has a reasonable structural design.

[0025] In this embodiment, an internal threaded section 12 and a non-threaded section 13 are provided in the upper and lower parts of the interior of the limiting member 11. The inner diameter of the internal threaded section 12 is smaller than the inner diameter of the non-threaded section 13. The top of the outer end of the piston rod 8 at the lower end is set as an external threaded section 14 with a small diameter. The external threaded section 14 is threadedly connected and matched with the internal threaded section 12. The inner diameter of the non-threaded section 13 is matched with the diameter of the smooth section of the piston rod 8 at the lower end. The design of the above structure enables the limiting member 11 to be threadedly connected and matched with the outer end of the piston rod 8 at the lower end. That is to say, the spacing between the limiting member 11 and the rear end cover 5 is adjusted by screwing in or out. The spacing adjustment of the limiting member 11 is convenient and simple. At the same time, a non-threaded section 13 with a larger inner diameter is provided below the internal threaded section 12 of the limiting member 11, and the smooth section on the piston rod 8 at the lower end is matched with the non-threaded section 13. Under the premise of ensuring stable limiting, this arrangement ensures that the limiting member 11 and the rear end cover 5 repeatedly contact and limit the collision force generated by the two will not cause the threaded structure to be damaged, thereby ensuring the service life.

[0026] In this embodiment, the inner surfaces of the front end cover 4 and the rear end cover 5 are both provided with a first annular cavity 15, and the through holes 9 are both formed in the center of the corresponding first annular cavity 15. The first annular cavity 15 is provided with a second sealing member 16 that forms a sealing contact with the outer peripheral surface of the corresponding piston rod 8. That is to say, the first annular cavity 15 of the front end cover 4 is installed with a second sealing member 16 that forms a sealing contact with the outer peripheral surface of the piston rod 8 at the upper end, and the first annular cavity 15 of the rear end cover 5 is also installed with a second sealing member 16 that forms a sealing contact with the outer peripheral surface of the piston rod 8 at the lower end. By setting the first annular cavity 15 and the second sealing member 16 in coordination, the sealing effect between the through hole 9 on the front end cover 4 and the piston rod 8 at the upper end, and between the through hole 9 on the rear end cover 5 and the piston rod 8 at the lower end is better.

[0027] In this embodiment, a second annular cavity 17 is correspondingly provided between the inner surfaces of the front end cover 4 and the rear end cover 5 and the relative surface of the piston 2. The second annular cavity 17 is arranged relative to the outer side of the first annular cavity 15. The second annular cavity 17 is used to install a flexible buffer 18. The flexible buffer can provide buffering protection for the piston 2, the front end 4 and the rear end cover 5, and also reduce the noise generated during movement. More specifically, the second annular cavity 17 can be provided on the inner surfaces of the front end cover 4 and the rear end cover 5 and on the upper and lower surfaces of the piston 2. This arrangement has a better buffering effect and also reduces the weight of the front end cover 4, the rear end cover 5 and the piston 2.

[0028] In this embodiment, at least one first annular groove 19 and at least one second annular groove 20 are provided on the outer peripheral surface of the piston 2. The first annular groove 19 is used to install the third sealing member 21. Through the coordinated arrangement of the first annular groove 19 and the third sealing member 21, the piston 2 divides the cavity into two upper and lower closed chambers, so that the movement of the piston 2 is more stable. The second annular groove 20 is located below the first annular groove 19 and is used to install the support ring 22. The support ring 222 can realize the function of supporting the piston to prevent axial deviation, thereby further reducing the noise generated during movement.

[0029] In this embodiment, axial holes 23 corresponding to the through holes 9 on the front cover 4 and the rear cover 5 are provided on the upper and lower surfaces of the piston 2. The axial holes 23 realize the effective fixation of the two pistons 2, and a hollow hole 24 that penetrates and communicates is provided at the bottom center of the two axial holes 23. The provision of the hollow hole 24 achieves the purpose of further reducing the weight of the piston 2. At the same time, a third annular groove 25 is provided on the end of the piston rod 8 that cooperates with the axial hole 23. The third annular groove 25 is used to install the fourth sealing member 26. More specifically, the third annular groove 25 is provided at the end of the upper piston rod 8 that cooperates with the corresponding axial hole 23. Only by such a provision, the gas in the chambers on both sides of the piston 2 will not flow through, thereby ensuring the sealing effect and achieving an overall good sealing effect.

[0030] In this embodiment, the outer circumferential surfaces of the front end cover 4 and the rear end cover 5 are further provided with a fourth annular groove 27, and the fourth annular groove 27 is used to install the fifth sealing member 28. That is to say, the front end cover 4 and the rear end cover 5 achieve the sealing of the two ends of the cavity 3 through the cooperation of the fourth annular groove 27 and the fifth sealing member 28. An annular limiting boss 29 is also formed on the outer side of the fourth annular groove 27, and an annular limiting recess 30 that cooperates with the annular limiting boss 29 is provided at the upper and lower ends of the cavity 3. The fifth annular groove 31 is used to place the snap ring 32. The snap ring 32 is a C-shaped structure. During installation, the front end cover 4 and the rear end cover 5 are placed in the upper and lower ends of the cavity 3. At this time, the annular limiting boss 29 will form a limiting fit with the bottom of the annular limiting recess 30, thereby limiting the installation position of the front end cover 4 and the rear end cover 5. Then, the snap ring 32 is deformed by force through a tool and placed in the corresponding fifth annular groove 31. After the snap ring 32 is subjected to force, the front end cover 4 and the rear end cover 5 can be fixed.

[0031] In this example, a sixth annular groove 33 is provided in the through holes of the front end cover 4 and the rear end cover 5 , and the first sealing member 10 is installed in the sixth annular groove 33 .

[0032] The above contents are further detailed descriptions of the present invention in combination with specific preferred implementations, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A double-rod large-bore cylinder, characterized in that: The invention comprises a cylinder body (1) and a piston (2), wherein the cylinder body (1) is provided with a cavity (3) with two ends thereof penetrating therethrough, and the two ends of the cavity (3) are respectively sealedly connected with a front end cover (4) and a rear end cover (5), wherein the cylinder body (1) is provided with a first air hole (6) at a position below the front end cover (4), and the cylinder body (1) is provided with a second air hole (7) at a position above the rear end cover (5), wherein the first air hole (6) and the second air hole (7) are both connected to the cavity (3), and the outer peripheral surface of the piston (2) can be slidably attached to the inner wall of the cavity (3), Both ends of the piston (2) are connected to piston rods (8), and the front end cover (4) and the rear end cover (5) are provided with through holes (9) for the corresponding piston rods (8) to pass through, and the through holes (9) are also provided with a first sealing member (10) that forms a sealing contact with the outer peripheral surface of the corresponding piston rod (8), and the outer end of the piston rod (8) located at the lower end is also provided with a limiting member (11) that cooperates with the rear end cover (5) to limit the position, and the limiting member (11) can move along the length direction of the corresponding piston rod (8) so that the distance between it and the rear end cover (5) is adjustable.

2. A double-rod large-bore cylinder according to claim 1, characterized in that: The interior of the limiting member (11) is provided with an internal thread section (12) and a non-thread section (13) at the upper and lower parts, the inner diameter of the internal thread section (12) is smaller than the inner diameter of the non-thread section (13), and the corresponding outer end top of the piston rod (8) is provided with an external thread section (14) with a small diameter, the external thread section (14) is threadedly connected with the internal thread section (12), and the inner diameter of the non-thread section (13) is adapted to the diameter of the smooth section of the piston rod (8).

3. A double-rod large-bore cylinder according to claim 1, characterized in that: The inner surfaces of the front end cover (4) and the rear end cover (5) are both provided with a first annular cavity (15), the through hole (9) is formed at the center of the corresponding first annular cavity (15), and the first annular cavity (15) is provided with a second sealing member (16) which forms a sealing contact with the outer peripheral surface of the corresponding piston rod (8).

4. A double-rod large-bore cylinder according to claim 3, characterized in that: A second annular cavity (17) is provided between the inner surfaces of the front end cover (4) and the rear end cover (5) and the opposite surface of the piston (2). The second annular cavity (17) is arranged relative to the outer side of the first annular cavity (15). The second annular cavity (17) is used to install a flexible buffer (18).

5. A double-rod large-bore cylinder according to claim 1, characterized in that: At least one first annular groove (19) and at least one second annular groove (20) are provided on the outer peripheral surface of the piston (2); the first annular groove (19) is used for installing a third sealing member (21); the second annular groove (20) is located below the first annular groove (19) and is used for installing a supporting ring member (22).

6. A double-rod large-bore cylinder according to claim 1, characterized in that: The upper and lower surfaces of the piston (2) are provided with axial holes (23) corresponding to the through hole (9), the bottom center of the axial hole (23) is provided with a hollow hole (24) that penetrates and communicates with each other, and the end of the piston rod (8) that cooperates with the axial hole (23) is provided with a third annular groove (25), and the third annular groove (25) is used to install a fourth sealing member (26).

7. A double-rod large-bore cylinder according to claim 1, characterized in that: The outer circumferential surfaces of the front end cover (4) and the rear end cover (5) are also provided with a fourth annular groove (27) and an annular limiting boss (28) located outside the fourth annular groove (27); the fourth annular groove (27) is used to install a fifth sealing member (29); an annular limiting recess (30) matching the annular limiting boss (28) is provided at the corresponding end of the cavity (3); a fifth annular groove (31) is provided at the root of the annular limiting recess (30); the fifth annular groove (31) is used to place a retaining ring (32).

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