Hydraulic machine cushion cylinder

Abstract

The buffer cylinder comprises a cylinder body, a cylinder bottom for sealing the cylinder body is arranged at the lower end of the cylinder body, a piston is arranged in an inner cavity of the cylinder body, the piston is in a step shape, the upper end of the piston extends out of a cylinder opening guide sleeve, a piston threaded hole with an upward opening is formed in the axis of the piston, and a center screw is connected in the piston threaded hole in a screwed mode. A screw counter bore with a downward opening is formed along the axis of the center screw, a main spring is arranged in the screw counter bore, the bottom of the main spring is supported in the center of the bottom wall of the piston threaded hole, the top of the main spring is supported in a spring seat, and the periphery of the spring seat is in clearance fit with the inner wall of the upper portion of the screw counter bore. And the top center of the spring seat is supported at the top wall center of the screw counter bore through a thrust ball bearing. The hydraulic machine cushion cylinder can provide back pressure for the sliding block in the tearing process when the sliding block impacts and cuts a plate, impact force is reduced, noise is lowered, and meanwhile a die is prevented from being damaged.

Description

Technical Field

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

[0002] Hydraulic press is a device that uses hydraulic transmission technology to perform pressure processing. Compared with mechanical presses, it is more suitable for sheet bending, flanging, fine blanking, cold extrusion of metal parts, and precision press-fitting of parts. Hydraulic presses usually include left and right columns, the tops of which are connected by an upper crossbeam, the bottoms of which are connected to a workbench, a slider is provided between the upper crossbeam and the workbench, and a main cylinder is installed at the center of the upper crossbeam; an upper die is installed at the lower end of the slider, and a lower die is installed on the workbench. The main cylinder drives the slider downward to close the upper die and the lower die to press the workpiece.

[0003] After the sheet is pressed and formed, it needs to be punched and trimmed. Traditionally, it is necessary to complete the pressing and punching and trimming on two hydraulic presses respectively, which has low efficiency and large workload. In addition, when the slider moves down quickly to cut the sheet, one-third of the thickness of the sheet is cut off, and the remaining two-thirds of the thickness is torn. During the tearing process, the impact force is too large under the slider without back pressure, which can easily damage the blade of the mold and even cause chipping. Utility Model Content

[0004] The purpose of this section is to summarize some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and utility model name of this application to avoid blurring the purpose of this section, specification abstract and utility model name, and such simplifications or omissions cannot be used to limit the scope of the utility model.

[0005] In view of the above problems and / or the problems existing in the prior art, the present utility model is proposed.

[0006] The purpose of the utility model is to overcome the problems existing in the prior art and provide a hydraulic press buffer cylinder, which can provide back pressure for the slider during the tearing process when the slider punches and cuts the sheet material, reduce the impact force, reduce the noise and avoid damage to the mold.

[0007] In order to solve the above technical problems, the utility model provides a hydraulic press buffer cylinder, including a cylinder body, a cylinder bottom for sealing the cylinder body at the lower end, a piston being provided in the inner cavity of the cylinder body, the piston being step-shaped and the upper end extending from the cylinder mouth guide sleeve, a piston threaded hole opening upward being provided along the piston axis, a center screw being screwed in the piston threaded hole, a screw countersunk hole opening downward being provided along the axis of the center screw, a main spring being provided in the screw countersunk hole, the bottom of the main spring being supported at the center of the bottom wall of the piston threaded hole, the top of the main spring being supported in a spring seat, the outer periphery of the spring seat being clearance-matched with the upper inner wall of the screw countersunk hole; the top center of the spring seat being supported at the center of the top wall of the screw countersunk hole through a thrust ball bearing.

[0008] As an improvement of the utility model, support springs are respectively embedded in the countersunk holes on the lower end surface of the piston. The support springs are symmetrically arranged and the lower ends are respectively located in the through holes of the cylinder bottom and supported on the central boss of the blind flange. The blind flange is fixed in the countersunk holes at the cylinder bottom by screws.

[0009] As a further improvement of the present invention, the cylinder mouth guide sleeve includes a guide sleeve and a fastening sleeve, the bottom outer edge of the guide sleeve is supported on the inner step of the cylinder body, and the bottom inner edge of the guide sleeve is located above the outer step of the piston; the fastening sleeve is screwed into the upper end screw hole of the cylinder body, and the bottom of the fastening sleeve is pressed on the outer step of the guide sleeve.

[0010] As a further improvement of the utility model, the bottom of the piston is eccentrically connected to two guide rods extending downward, the lower ends of the two guide rods are respectively inserted into the guide holes at the bottom of the cylinder, and the lower ends of the two guide holes are respectively provided with sealing flanges to close them.

[0011] As a further improvement of the utility model, a through central exhaust hole is provided at the top center of the central screw and the spring seat, and a radial air guide hole is provided on the side wall of the cylinder body to communicate with the upper cavity of the sealing section of the piston.

[0012] As a further improvement of the utility model, the buffer stroke of the piston is 50 mm, and the adjustable stroke of the central screw is 250 mm.

[0013] Compared with the prior art, the utility model has achieved the following beneficial effects: 1. When the slider moves downward and the upper and lower dies cooperate to cut the plate into pieces and enter the tearing process, the top of the central screw of the buffer cylinder is supported under the slider to buffer it; the central screw can rotate in the piston to adjust its exposed height, so as to accurately match the stroke of the slider;

[0014] 2. When the center screw is rotated to adjust the height, the supporting force of the main spring can balance the weight of the center screw thread, making it easy and quick to rotate and adjust; the spring seat can prevent the main spring from tilting, and the thrust ball bearing on its top can further reduce the torque of the center screw when adjusting the height;

[0015] 3. When the slider moves downward, the piston is forced to move downward. After the slider moves upward, the tension of the support spring lifts the piston until the outer step of the piston abuts against the bottom of the guide sleeve. The guide sleeve guides and stabilizes the upper piston rod of the piston. The eccentric guide rod slides along the guide hole at the bottom of the cylinder, which also has a forced guiding effect on the lower part of the piston, ensuring that the support spring is compressed or extended along its own axis to avoid failure.

[0016] 4. After installing the buffer cylinder on both sides of the workbench, the same hydraulic press can be used to complete the pressing and forming first; after changing the mold, the punching and trimming can be continued, which greatly improves the work efficiency and reduces the workload of changing equipment and cutting. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. The drawings are only provided for reference and explanation, not for limiting the present utility model. Among them:

[0018] Figure 1 This is a structural schematic diagram of the buffer cylinder of the hydraulic press of the utility model;

[0019] In the figure: 1. Cylinder body; 1a. Oil filling port; 1b. Radial air guide hole; 2. Piston; 3. Guide sleeve; 4. Fastening sleeve; 5. Center screw; 5a. Center exhaust hole; 6. Main spring; 7. Spring seat; 7a. Thrust ball bearing; 8. Support spring; 9. Guide rod; 10. Stuffing flange. DETAILED DESCRIPTION

[0020] In the following description of the utility model, the terms "upper", "lower", "front", "back", "left", "right", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the utility model and simplifying the description, and do not mean that the device must have a specific direction.

[0021] In order to make the technical means, creative features, objectives and effects of the present invention easier to understand, the present invention is further described below with reference to specific figures. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0023] like Figure 1 As shown, the hydraulic press buffer cylinder of the utility model adopts a plunger cylinder structure including a cylinder body 1, a piston 2, a guide sleeve 3, a fastening sleeve 4, a center screw 5, a main spring 6 and a support spring 8. The lower end of the cylinder body 1 is provided with a cylinder bottom to close it, and the inner cavity of the cylinder body 1 is provided with a piston 2, and the buffer stroke h1 of the piston 2 is 50mm. The piston 2 is stepped and the upper end extends from the cylinder port guide sleeve. The cylinder port guide sleeve includes a guide sleeve 3 and a fastening sleeve 4. The bottom outer edge of the guide sleeve 3 is supported on the inner step of the cylinder body 1, and the bottom inner edge of the guide sleeve 3 is located above the outer step of the piston 2; the fastening sleeve 4 is screwed into the upper end screw hole of the cylinder body 1, and the bottom of the fastening sleeve 4 is pressed on the outer step of the guide sleeve 3. The lower circumference of the cylinder body 1 is provided with an oil filling port 1a that communicates with the lower cavity space of the piston 2.

[0024] A piston threaded hole opening upward is provided along the piston axis, and a center screw 5 is screwed into the piston threaded hole. The adjustable stroke h2 of the center screw 5 is 250 mm, which is convenient for adjusting the height according to the stroke of the slider. A screw countersink opening downward is provided along the axis of the center screw 5, and a main spring 6 is provided in the screw countersink. The bottom of the main spring 6 is supported at the center of the bottom wall of the piston threaded hole, and the top of the main spring 6 is supported in the spring seat 7. The outer periphery of the spring seat 7 is clearance-matched with the upper inner wall of the screw countersink; the top center of the spring seat 7 is supported at the center of the top wall of the screw countersink through a thrust ball bearing 7a, which is convenient for the relative rotation between the center screw 5 and the main spring 6, making the rotation adjustment of the center screw 5 easy and convenient.

[0025] Support springs 8 are respectively embedded in the countersunk holes on the lower end surface of the piston 2. Multiple support springs 8 are symmetrically arranged, and the lower ends are respectively located in the through holes at the bottom of the cylinder and supported on the central boss of the blind flange 10. The blind flange 10 is fixed in the countersunk hole at the bottom of the cylinder by screws. The function of the support spring 8 is to lift the piston 2 when the slider is depressurized and returns. Two guide rods 9 extending downward are connected to the bottom of the piston 2. The lower ends of the two guide rods 9 are respectively inserted into the guide holes at the bottom of the cylinder to guide the piston 2. The lower ends of the two guide holes are respectively provided with blind flanges 10 to close them. The guide holes and guide rods 9 deviate from the axis of the cylinder body 1 to facilitate forced guidance.

[0026] A through ø16 center exhaust hole 5a is provided at the center of the top of the center screw 5 and the spring seat 7 to prevent air holding when adjusting the stroke; a radial air guide hole 1b is provided on the side wall of the cylinder body 1 to communicate with the upper cavity of the sealing section of the piston 2, and a muffler is installed to reduce noise pollution.

[0027] The cylinder body 1 is manufactured by adopting the mature submerged arc welding process. The Q345 material cylinder barrel and the cylinder bottom chamfer are butt-jointed by submerged arc welding. After the cylinder bottom is processed with a step, it is inserted into the bottom of the cylinder body 1, which effectively prevents welding slag from falling into the cylinder barrel and increasing the difficulty of later cleaning. H08A welding wire and flux are used for welding. After welding, the corresponding countersunk holes are processed on the cylinder bottom by the machining center for installing the limit rod and the support spring 8.

[0028] The piston 2 is also made by submerged arc welding and processed according to the size requirements of the drawing. The piston 2 is installed in the cylinder body 1 and sealed by a grid ring and a YX sealing ring. The fastening sleeve 4 is matched with the internal thread of the upper port of the cylinder body through the external thread, and the guide sleeve 3 is pressed tightly in the cylinder body.

[0029] Usually, six blind flanges are evenly distributed along the center of the cylinder bottom for installing the support spring 8. At the same time, a guide hole is processed on the cylinder bottom, and the lower end of the guide hole is also blocked with a blind flange.

[0030] The above description is only the preferred feasible embodiment of the utility model, which shows and describes the basic principle, main features and advantages of the utility model, but does not limit the scope of patent protection of the utility model. The technicians in this industry should understand that the utility model is not limited by the above embodiments. In addition to the above embodiments, the utility model can also have other implementation modes without departing from the spirit and scope of the utility model. The utility model will also have various changes and improvements. All technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the utility model. The scope of protection required by the utility model is defined by the attached claims and their equivalents. The technical features not described in the utility model can be achieved by or using existing technologies, which will not be repeated here.

Claims

1. A hydraulic press buffer cylinder, comprising a cylinder body, a cylinder bottom for sealing the cylinder body is provided at the lower end of the cylinder body, and a piston is provided in the inner cavity of the cylinder body, characterized in that: The piston is stepped and its upper end extends out from the cylinder guide sleeve. A piston threaded hole opening upward is provided along the piston axis. A center screw is screwed in the piston threaded hole. A screw countersunk hole opening downward is provided along the axis of the center screw. A main spring is provided in the screw countersunk hole. The bottom of the main spring is supported at the center of the bottom wall of the piston threaded hole. The top of the main spring is supported in a spring seat. The outer periphery of the spring seat is clearance-matched with the upper inner wall of the screw countersunk hole. The top center of the spring seat is supported at the center of the top wall of the screw countersunk hole through a thrust ball bearing.

2. The hydraulic press buffer cylinder according to claim 1, characterized in that: Support springs are respectively embedded in the countersunk holes on the lower end surface of the piston. The support springs are symmetrically arranged and the lower ends are respectively located in the through holes of the cylinder bottom and supported on the central boss of the blind flange. The blind flange is fixed in the countersunk holes at the cylinder bottom by screws.

3. The hydraulic press buffer cylinder according to claim 1, characterized in that: The cylinder port guide sleeve includes a guide sleeve and a fastening sleeve, the bottom outer edge of the guide sleeve is supported on the inner step of the cylinder body, and the bottom inner edge of the guide sleeve is located above the outer step of the piston; the fastening sleeve is screwed into the upper end screw hole of the cylinder body, and the bottom of the fastening sleeve is pressed on the outer step of the guide sleeve.

4. The hydraulic press buffer cylinder according to claim 1, characterized in that: The bottom of the piston is eccentrically connected with two guide rods extending downwards, the lower ends of the two guide rods are respectively inserted into the guide holes at the bottom of the cylinder, and the lower ends of the two guide holes are respectively provided with sealing flanges for closing them.

5. The hydraulic press buffer cylinder according to claim 1, characterized in that: A through central exhaust hole is arranged at the center of the top of the central screw rod and the spring seat, and a radial air guide hole is arranged on the side wall of the cylinder body to communicate with the upper cavity of the sealing section of the piston.

6. The hydraulic press buffer cylinder according to claim 1, characterized in that: The buffer stroke of the piston is 50 mm, and the adjustable stroke of the central screw is 250 mm.

Images