Pneumatic buffer type linear motor

Abstract

The utility model discloses a pneumatic buffer type linear motor, which relates to the technical field of linear motors and comprises a base, a stator and a rotor. The stator is fixedly mounted between the guide rails; the rotor is fixedly connected with a sliding seat; the sliding seat is in sliding fit with the guide rail through a sliding block; a pneumatic buffering device is arranged on the base and is a friction-free or low-friction air cylinder, and a piston rod of the air cylinder is connected with the sliding seat through a bolt. When the linear motor moves in the vertical direction, the pneumatic buffer device does not add resistance in the moving process through the air suspension effect, and the friction-free or low-friction effect is achieved. And under the power failure working condition, the air cylinder can provide a buffering effect, and mechanical impact caused by power failure is prevented. Through the design, the motion precision of the linear motor can be ensured, and equipment can be protected during power failure.

Description

Technical Field

[0001] The utility model relates to the technical field of linear motors, in particular to a pneumatic buffer type linear motor. Background Art

[0002] A linear motor is an electric motor that converts electrical energy directly into linear motion. Compared with traditional rotary motors that obtain linear motion, linear motors have the advantages of fast response speed and high precision because they eliminate devices such as ball screws, racks and pinions, worm gears, or crank slider mechanisms. They are widely used in industrial automation, transportation, medical equipment and other fields. When the linear motor is installed vertically, due to the effect of current, the linear motor has closed-loop control and can be fixed in the vertical direction. However, in a power-off condition, it is necessary to prevent the linear motor from continuing to move downward due to its own gravity, so that the linear motor collides with the end, affecting its use. Usually, a magnetic device or gas spring is installed. For example, Patent No. 202222834829.4 discloses a linear motor structure for vertical use of the Z axis. The linear motor uses a magnetically attracted magnetic sleeve and a magnetic rod for buffering. However, the carrying capacity of the magnetic buffer device may be limited by the magnetic field strength and the magnetic material, and is more susceptible to the influence of the external magnetic field. Patent No. 201920274148.2 discloses a linear motor with a buffer mechanism, wherein the buffer structure of the linear motor is preferably a gas spring, and the gas spring buffer will transmit vibration to the linear motor. In addition, the buffer devices in the above patents will generate resistance during the normal operation of the linear motor, affecting the motion accuracy of the linear motor.

[0003] Pneumatic transmission has the advantages of simple structure, easy access to energy, and adjustable system stiffness, so it has good applicability in static and dense motion systems. As the actuator in the pneumatic transmission system, the cylinder plays an important role in pneumatic transmission. The linear motor has the advantage of high precision due to its low friction characteristics, but there is friction between the piston and the cylinder of an ordinary cylinder. The use of this cylinder to design a buffer device will affect the accuracy of the linear motor.

[0004] In view of this, the inventor proposes the following technical solution. Utility Model Content

[0005] 1. Technical problems to be solved by the utility model

[0006] In order to overcome the deficiencies of the prior art, the purpose of the utility model is to provide a pneumatic buffer type linear motor, which can not be affected by resistance in normal operation and can prevent its own gravity from causing the linear motor to collide in power-off conditions.

[0007] 2. Technical solution

[0008] In order to solve the above problems, the technical solution provided by the utility model is: a pneumatic buffer type linear motor, including a base, a sliding seat, a mover, a stator, a guide rail, a slider, and a pneumatic buffer device, characterized in that: guide rails are fixedly connected to both sides of the base; the stator is installed between the guide rails; a sliding seat is fixedly connected to the mover; the sliding seat achieves sliding cooperation with the guide rail through the slider; a pneumatic buffer device is arranged on the base, and the pneumatic buffer device provides a buffer force that does not affect the accuracy of the linear motor during normal operation and prevents the motor from continuing to move due to its own gravity under power-off conditions.

[0009] Furthermore, the pneumatic buffer device is a frictionless or low-friction cylinder, comprising an outer cylinder, an inner cylinder, a piston, a piston rod, a front end cover, and a rear end cover; the piston rod is connected to the piston by bolts, and the piston is installed in the inner cylinder, and its diameter is smaller than the diameter of the inner cylinder; the inner cylinder is installed in the outer cylinder and a certain radial gap is left between the inner cylinder and the outer cylinder; the front end cover is installed at the front end of the outer cylinder and is provided with a front air inlet, the rear end cover is installed at the rear end of the outer cylinder and is provided with a rear air inlet, and an air floating air inlet is installed on the side of the outer cylinder close to the rear end cover.

[0010] Furthermore, the pneumatic buffer device is provided with two, which are respectively located on both sides of the sliding seat and are threadedly connected to the sliding seat through a piston rod.

[0011] Furthermore, the inner cylinder is radially perforated along its outer circumferential surface to form throttling holes, and the throttling holes are arranged one by one in the axial direction of the inner cylinder.

[0012] Furthermore, a circle of grooves is provided near the middle of the outer cylindrical surface of the piston and the grooves are arranged on the side close to the rear end cover, blind holes are radially drilled on the grooves, and then through holes are drilled along the side of the piston close to the piston rod to form a pressure relief groove.

[0013] Furthermore, the front end cover, the rear end cover and both ends of the outer cylinder are sealed by O-rings made of rubber, resin or silicone.

[0014] Furthermore, a certain slope is provided on a side of the groove close to the rear end cover.

[0015] Furthermore, the front air inlet of the front end cover, the rear air inlet of the rear end cover and the air flotation air inlet are all connected to the atmosphere.

[0016] Furthermore, the front air inlet and the rear air inlet are both connected to a two-position three-way electromagnetic reversing valve.

[0017] 3. Beneficial effects

[0018] Compared with the prior art, the technical solution provided by the utility model has the following beneficial effects:

[0019] (1) A pneumatically cushioned linear motor is proposed in an embodiment of the present application. An air flotation air inlet is provided on the outer cylinder barrel of the air cylinder. The gas entering the inner cylinder barrel through the throttle hole on the inner cylinder barrel forms an air film between the piston and the inner cylinder barrel, so that the piston is suspended, so that the linear motor does not generate friction resistance during movement, thereby preventing the accuracy of the linear motor from being affected.

[0020] (2) The embodiment of the present application proposes a pneumatic buffer type linear motor. When the linear motor is in a power-off condition, the frictionless or low-friction cylinder can achieve a buffering effect by relying on the resistance generated by the compressed air. At the same time, the gas in the high-pressure chamber can enter the low-pressure chamber through the pressure relief groove on the piston, thereby not affecting the air film and achieving high control accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0022] Figure 2 It is a partial structural schematic diagram of the utility model.

[0023] Figure 3 It is a half-section view of the pneumatic buffer device.

[0024] Figure 4 This is a three-dimensional structural diagram of the inner cylinder.

[0025] Figure 5 Schematic diagram of the piston structure.

[0026] Figure 6 for Figure 5 AA cross-section diagram.

[0027] Figure 7 for Figure 5 BB cross-section diagram.

[0028] In the figure, 1, base; 2, sliding seat; 3, mover; 4, stator; 5, guide rail; 6, slider; 7, pneumatic buffer device; 70, O-ring; 71, piston rod; 72, front end cover; 73, front air inlet; 74, outer cylinder; 75, inner cylinder; 76, piston; 77, air floatation air inlet; 78, rear air inlet; 79, rear end cover; 751, throttle hole; 761, blind hole; 762, pressure relief groove. DETAILED DESCRIPTION

[0029] The present application is further described in detail below in conjunction with the accompanying drawings and implementation methods. It is understood that the specific implementation methods described herein are only used to explain the relevant utility model, rather than to limit the utility model. It is also necessary to say that, for the convenience of description, only the parts related to the utility model are shown in the accompanying drawings. It should be noted that, in the absence of conflict, the implementation methods in the present application and the features in the implementation methods can be combined with each other. In the description of the present utility model, it should be noted that the orientation or position relationship indicated by the terms "front", "rear", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0030] Implementation method:

[0031] Reference Figure 1 and Figure 2 The utility model discloses a pneumatic buffer linear motor, comprising a base 1, a sliding seat 2, a mover 3, a stator 4, a guide rail 5, a slider 6, and a pneumatic buffer device 7. Guide rails 5 are fixedly connected to both sides of the base 1; the stator 4 is installed between the guide rails 5; the mover 3 is fixedly connected to the sliding seat 2; the sliding seat 2 is slidably matched with the guide rail 5 through the slider 6; a pneumatic buffer device 7 is arranged on the base 1, and the pneumatic buffer device 7 provides a buffer force that does not affect the accuracy of the linear motor during normal operation and prevents the motor from continuing to move due to its own gravity under power-off conditions.

[0032] Reference Figure 3 The pneumatic buffer device 7 is a frictionless or low-friction cylinder, including an outer cylinder 74, an inner cylinder 75, a piston 76, a piston rod 71, a front end cover 72, and a rear end cover 79; the piston rod 71 is connected to the piston 76 by bolts, and the piston 76 is installed in the inner cylinder 75, and its diameter is smaller than the diameter of the inner cylinder 75. The inner cylinder 75 is installed in the outer cylinder 74 and a certain radial gap is left between the inner cylinder 75 and the outer cylinder 74; the front end cover 72 is installed at the front end of the outer cylinder 74 and is provided with a front air inlet 73, the rear end cover 79 is installed at the rear end of the outer cylinder 74 and is provided with a rear air inlet 78, and the outer cylinder 74 is provided with an air floating air inlet 77 on the side close to the rear end cover 79.

[0033] The front air inlet 73 of the front end cover 72, the rear air inlet 78 of the rear end cover 79 and the air floating air inlet 77 are all connected to the atmosphere.

[0034] The front cover 72, the rear cover 79 and the two ends of the outer cylinder 74 are sealed by O-rings 70 made of rubber, resin or silicone. Rubber, resin or silicone have good elasticity and toughness and are the preferred materials for sealing. The use of O-rings improves the sealing between the piston and the cylinder and prevents the piston from deflecting during movement.

[0035] Reference Figure 1 and Figure 2 The pneumatic buffer device 7 is provided with two, which are respectively arranged on both sides of the sliding seat 2 and are threadedly connected to the sliding seat 2 through the piston rod 71. In this way, under the power-off condition, the two pneumatic buffer devices can provide buffering force for both sides of the sliding seat respectively, making the buffering process more stable.

[0036] Reference Figures 4 to 7 The inner cylinder 75 is radially perforated along its outer circumferential surface to form a throttling hole 751, and the throttling holes 751 are arranged one by one in the axial direction of the inner cylinder 75; a circle of grooves 760 are provided near the middle position of the outer cylindrical surface of the piston 76, and the grooves 760 are arranged on the side close to the rear end cover 79, a blind hole 761 is radially punched on the groove 760, and then a through hole is punched along the side of the piston 76 close to the piston rod 71 to form a pressure relief groove 762; and the groove 760 is provided with a certain slope on the side close to the rear end cover 79.

[0037] Working principle of this utility model:

[0038] When the linear motor is working normally, air is ventilated to the outer cylinder 74 through the air floatation air inlet 77, and then enters the gap between the outer cylinder 74 and the inner cylinder 75, and forms an air film between the piston 76 and the inner cylinder 75 through the throttle hole 751, so that the piston is suspended; the air inlet holes 73 and 78 on the front cover 72 and the rear cover 79 are connected to the two-position three-way electromagnetic reversing valve, and the electromagnetic reversing valve is connected to the atmosphere at this time. The pressure before and after the piston is equal, and the linear motor pushes the piston rod 71 to move without resistance. The movement accuracy of the linear motor is guaranteed. When the linear motor is in a power-off state, adjust the electromagnetic reversing valve so that the two sides of the cylinder are no longer ventilated. At this time, the piston rod 71 driven by the linear motor squeezes the gas in the cylinder, and the piston 76 is buffered by the damping effect of the gas. At this time, the side close to the rear end cover 79 is a high-pressure chamber, and the side of the front end cover 72 is a low-pressure chamber. There is a groove 760 with a certain slope close to the high-pressure chamber. Therefore, the gas in the high-pressure chamber can enter the low-pressure chamber through the pressure relief groove 762 without flowing out from the gap between the inner cylinder 75 and the piston 76, and will not affect the air film.

[0039] The above schematically describes the present invention and its implementation methods, which are not restrictive. The drawings show only one implementation method of the present invention, and the actual structure is not limited thereto. Therefore, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A pneumatic buffer type linear motor, comprising a base (1), a sliding seat (2), a mover (3), a stator (4), a guide rail (5), a slider (6), and a pneumatic buffer device (7), characterized in that: Guide rails (5) are fixedly connected to both sides of the base (1); the stator (4) is installed between the guide rails (5); a sliding seat (2) is fixedly connected to the mover (3); the sliding seat (2) and the guide rail (5) are slidably matched through a slider (6); a pneumatic buffer device (7) is arranged on the base (1), and the pneumatic buffer device (7) comprises an outer cylinder (74), an inner cylinder (75), a piston (76), a piston rod (71), a front end cover (72), and a rear end cover (79); the piston rod (71) and the piston (76) are connected by bolts. The piston (76) is installed in the inner cylinder (75) and has a diameter slightly smaller than that of the inner cylinder (75). The inner cylinder (75) is installed in the outer cylinder (74) and a certain radial gap is left between the inner cylinder (75) and the outer cylinder (74). The front end cover (72) is installed at the front end of the outer cylinder (74) and is provided with a front air inlet (73). The rear end cover (79) is installed at the rear end of the outer cylinder (74) and is provided with a rear air inlet (78). The outer cylinder (74) is provided with an air-floating air inlet (77) on one side close to the rear end cover (79).

2. A pneumatic buffer linear motor according to claim 1, characterized in that: The pneumatic buffer device (7) is provided with two, which are respectively located on both sides of the sliding seat (2), and are threadedly connected to the sliding seat (2) via a piston rod (71).

3. A pneumatic buffer linear motor according to claim 1, characterized in that: The inner cylinder (75) is radially perforated along its outer circumferential surface to form throttling holes (751), and the throttling holes (751) are arranged one by one in the axial direction of the inner cylinder (75).

4. The pneumatic buffer linear motor according to claim 1, characterized in that: A circle of grooves (760) is provided near the middle of the outer cylindrical surface of the piston (76), and the grooves (760) are arranged on the side close to the rear end cover (79). A blind hole (761) is radially drilled on the grooves (760), and then a through hole is drilled along the side of the piston (76) close to the piston rod (71) to form a pressure relief groove (762).

5. The pneumatic buffer linear motor according to claim 1, characterized in that: The front end cover (72), the rear end cover (79) and both ends of the outer cylinder (74) are sealed by an O-ring (70) made of rubber, resin or silicone.

6. The pneumatic buffer linear motor according to claim 1, characterized in that: The front air inlet (73) of the front end cover (72), the rear air inlet (78) of the rear end cover (79) and the air flotation air inlet (77) are all connected to the atmosphere.

7. A pneumatic buffer linear motor according to claim 4, characterized in that: The groove (760) is provided with a certain slope on a side close to the rear end cover (79).

8. The pneumatic buffer linear motor according to claim 1, characterized in that: The front air inlet (73) and the rear air inlet (78) are connected to a two-position three-way electromagnetic reversing valve.

Images