Digital hydraulic cylinder

Abstract

The utility model relates to the technical field of hydraulic cylinders, and discloses a digital hydraulic cylinder which is composed of a hydraulic cylinder body, a lead screw, a piston, a piston rod, a containing cavity and the like, a magnetic block is fixedly arranged in the lead screw, an air bag is fixedly connected in the piston rod, and the inner side wall of the air bag is flush with the side wall of the containing cavity. According to the utility model, the magnetic fluid is filled in the air bag, and the inner side wall of the air bag is designed to be flush with the side wall of the placing cavity, so that when the screw rod drives the piston to move, as the screw rod is positioned in the placing cavity, the magnetic block in the screw rod is also positioned in the placing cavity, and the magnetic fluid in the air bag is positioned in the magnetic field range of the magnetic block; when the piston rod is in a stopping state, the magnetic block can adsorb magnetic fluid in the air bag, so that the air bag is attached to the spiral teeth of the lead screw, the lead screw is limited, the situation that the piston rod shakes after being stopped due to a gap between the lead screw and the piston is avoided, and the stability of the piston rod is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic cylinders, in particular to a digital hydraulic cylinder. Background Art

[0002] The digital hydraulic cylinder has completely digital motion characteristics. The frequency of the electric pulse corresponds to the movement speed of the cylinder, and the number of electric pulses corresponds to the stroke of the cylinder. The digital hydraulic cylinder is a high-tech product that combines a stepper or servo motor, a hydraulic slide valve, and a closed-loop position feedback design inside the hydraulic cylinder and connects to the hydraulic oil source. All functions are directly transmitted through the digital pulse signal sent by the digital hydraulic cylinder controller or computer or programmable logic controller to complete the length vector control at different speeds.

[0003] During use, existing digital hydraulic cylinders often use a servo motor to control the lead screw to drive the movement of the piston, thereby using the movement of the piston to drive the piston rod to extend or retract. The stopping of the piston rod is also achieved by the lead screw. However, since the lead screw and the piston are threadedly connected, there must be a gap at the connection between the lead screw and the piston. These gaps will cause the piston rod to shake after stopping, thereby reducing the accuracy of the hydraulic cylinder. Utility Model Content

[0004] In view of the shortcomings of the existing digital hydraulic cylinders, the utility model provides a digital hydraulic cylinder, which has the advantages of increasing the stability of the piston rod after stopping, improving the accuracy of the digital hydraulic cylinder, increasing the oil return speed, shortening the contraction time of the hydraulic cylinder, and solving technical problems such as shaking of the piston rod after stopping.

[0005] The utility model provides the following technical solution: a digital hydraulic cylinder, including a hydraulic cylinder body, and also including:

[0006] A flange is fixedly mounted on the left end surface of the hydraulic cylinder body, an oil return integrated block is fixedly mounted on the middle of the left end surface of the flange, a servo motor is fixedly mounted on the middle of the left end surface of the oil return integrated block, and a screw rod is fixedly connected to the output end of the servo motor;

[0007] The piston is slidably connected to the inner cavity of the hydraulic cylinder body, a sealing strip is fixedly sleeved on the outer surface of the piston, the outer surface of the sealing strip is in sliding contact with the inner cavity side wall of the hydraulic cylinder body, a piston rod is fixedly installed in the middle of the right end surface of the piston, a placement cavity is opened inside the piston rod, and an oil return pipe is fixedly connected between the outer surface of the hydraulic cylinder body and the outer surface of the oil return integrated block.

[0008] Preferably, the interior of the screw rod includes:

[0009] The magnetic block is fixedly arranged inside the screw rod.

[0010] Preferably, the interior of the piston rod comprises:

[0011] The airbag is fixedly connected to the inside of the piston rod, the inner side wall of the airbag is flush with the side wall of the placement cavity, and the inside of the airbag is filled with magnetic fluid.

[0012] Preferably, the interior of the piston comprises:

[0013] A connecting hole is provided inside the piston;

[0014] A spring fixedly connected to the interior of the connecting hole;

[0015] A baffle, fixedly connected to the left end of the spring;

[0016] The aperture value on the left side of the connecting hole is smaller than the aperture value on the right side, and the diameter value of the baffle is larger than the aperture value on the left side of the connecting hole.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] 1. By designing the magnetic block and the airbag, a magnetic fluid is installed inside the airbag, and the inner wall of the airbag is designed to be flush with the side wall of the placement cavity. When the lead screw drives the piston to move, since the lead screw is inside the placement cavity, the magnetic block inside the lead screw is also inside the placement cavity and causes the magnetic fluid inside the airbag to be within the magnetic field range of the magnetic block. When the piston rod is in a stopped state, the magnetic block will adsorb the magnetic fluid inside the airbag, so that the airbag fits on the spiral teeth of the lead screw, thereby limiting the lead screw, avoiding the shaking of the piston rod after stopping due to the gap between the lead screw and the piston, and improving the stability of the piston rod.

[0019] 2. By designing the connecting hole, spring and baffle, when the screw drives the piston to move and causes the piston rod to retract, since the interior of the oil return integrated block is filled with hydraulic oil, the piston will squeeze the hydraulic oil inside the oil return integrated block, so that the baffle will be affected by the pressure of the hydraulic oil and overcome the potential energy of the spring to move, so that the baffle opens the connecting hole, so that the hydraulic oil inside the oil return integrated block can quickly return to the interior of the hydraulic cylinder, shortening the time for piston rod recovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the overall structure of the digital hydraulic cylinder of the utility model;

[0021] Figure 2 This is a schematic diagram of the internal structure of the digital hydraulic cylinder of the utility model;

[0022] Figure 3 This is a schematic diagram of the internal structure of the placement chamber of the utility model;

[0023] Figure 4It is a schematic diagram of the internal structure of the connecting hole of the utility model.

[0024] In the figure: 1. hydraulic cylinder body; 2. flange; 3. oil return integrated block; 4. servo motor; 5. screw rod; 51. magnet; 6. piston; 61. connecting hole; 62. spring; 63. baffle; 7. sealing strip; 8. piston rod; 81. airbag; 9. placement chamber; 10. oil return pipe. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] See also Figure 1-Figure 4 A digital hydraulic cylinder comprises a hydraulic cylinder body 1, a flange 2 is fixedly mounted on the left end surface of the hydraulic cylinder body 1, an oil return integrated block 3 is fixedly mounted in the middle of the left end surface of the flange 2, a servo motor 4 is fixedly mounted in the middle of the left end surface of the oil return integrated block 3, a screw rod 5 is fixedly welded on the output end of the servo motor 4, the screw rod 5 extends into the interior of the oil return integrated block 3 and the hydraulic cylinder body 1, a piston 6 is slidably connected to the inner cavity of the hydraulic cylinder body 1, the piston 6 is transmission sleeved on the outer surface of the screw rod 5, a sealing strip 7 is fixedly sleeved on the outer surface of the piston 6, the outer surface of the sealing strip 7 is in sliding contact with the inner cavity side wall of the hydraulic cylinder body 1, a piston rod 8 is fixedly mounted in the middle of the right end surface of the piston 6, a placement cavity 9 is opened in the interior of the piston rod 8, the screw rod 5 extends into the interior of the placement cavity 9, and an oil return pipe 10 is fixedly connected between the outer surface of the hydraulic cylinder body 1 and the outer surface of the oil return integrated block 3.

[0027] See also Figure 1-Figure 4 A magnetic block 51 is fixedly arranged inside the screw rod 5 .

[0028] See also Figure 1-Figure 4 The inside of the piston rod 8 is fixedly connected with an airbag 81, the inner wall of the airbag 81 is flush with the side wall of the placement cavity 9, and the inside of the airbag 81 is filled with magnetic fluid, ensuring that the magnetic block 51 can adsorb the magnetic fluid inside the airbag 81, so that the airbag 81 fits on the screw rod 5, thereby limiting the screw rod 5.

[0029] See also Figure 1-Figure 4A connecting hole 61 is opened inside the piston 6, and a spring 62 is fixedly connected inside the connecting hole 61. A baffle 63 is fixedly connected to the left end of the spring 62. The aperture value on the left side of the connecting hole 61 is smaller than the aperture value on the right side, and the diameter value of the baffle 63 is larger than the aperture value on the left side of the connecting hole 61. When the piston rod 8 retracts, the pressure of the hydraulic oil is used to prompt the baffle 63 to open the connecting hole 61, so that the hydraulic oil in the oil return integrated block 3 can quickly flow back to the inside of the hydraulic cylinder body 1.

[0030] Working principle: When the hydraulic cylinder body 1 needs to extend or retract, the servo motor 4 is turned on, the servo motor 4 drives the screw rod 5 to rotate, the screw rod 5 drives the piston 6 to move, and the piston 6 drives the piston rod 8 to move, thereby completing the extension or retraction of the piston rod 8. When the piston rod 8 is in a stopped state, the magnetic block 51 inside the piston rod 8 will absorb the magnetic fluid inside the airbag 81, so that the airbag 81 fits on the spiral teeth of the screw rod 5, thereby limiting the screw rod 5, avoiding the piston rod 8 in the stopped state due to the influence of the screw rod 5 and the piston 6. The clearance between the piston rod 8 and the return oil block 3 causes shaking, thereby improving the stability of the piston rod 8. Secondly, when the piston rod 8 is in the retracted state, the return oil integrated block 3 is full of hydraulic oil, and the movement of the piston 6 will squeeze the return hydraulic oil. At this time, the pressure of the hydraulic oil will pressurize the baffle 63, so that the baffle 63 overcomes the potential energy of the spring 62 and moves, thereby opening the connecting hole 61. After the connecting hole 61 is opened, the hydraulic oil in the return oil integrated block 3 will quickly enter the interior of the hydraulic cylinder body 1, thereby realizing rapid oil return and shortening the retraction time of the piston rod 8.

Claims

1. A digital hydraulic cylinder, comprising a hydraulic cylinder body (1), characterized in that: Also includes: A flange (2) is fixedly mounted on the left end surface of the hydraulic cylinder body (1); an oil return integrated block (3) is fixedly mounted in the middle of the left end surface of the flange (2); a servo motor (4) is fixedly mounted in the middle of the left end surface of the oil return integrated block (3); and a screw rod (5) is fixedly connected to the output end of the servo motor (4); A piston (6) is slidably connected to the inner cavity of the hydraulic cylinder body (1); a sealing strip (7) is fixedly sleeved on the outer surface of the piston (6); the outer surface of the sealing strip (7) is in sliding contact with the inner cavity side wall of the hydraulic cylinder body (1); a piston rod (8) is fixedly installed in the middle of the right end surface of the piston (6); a placement cavity (9) is provided inside the piston rod (8); and an oil return pipe (10) is fixedly connected between the outer surface of the hydraulic cylinder body (1) and the outer surface of the oil return integrated block (3).

2. A digital hydraulic cylinder according to claim 1, characterized in that: The interior of the screw rod (5) comprises: The magnetic block (51) is fixedly arranged inside the screw rod (5).

3. A digital hydraulic cylinder according to claim 2, characterized in that: The interior of the piston rod (8) comprises: The airbag (81) is fixedly connected to the inside of the piston rod (8), the inner side wall of the airbag (81) is flush with the side wall of the placement cavity (9), and the inside of the airbag (81) is filled with magnetic fluid.

4. A digital hydraulic cylinder according to claim 3, characterized in that: The interior of the piston (6) comprises: A connecting hole (61) is provided inside the piston (6); A spring (62) fixedly connected inside the connecting hole (61); A baffle (63) fixedly connected to the left end of the spring (62); The aperture value on the left side of the connecting hole (61) is smaller than the aperture value on the right side, and the diameter value of the baffle (63) is larger than the aperture value on the left side of the connecting hole (61).

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