Electric cylinder with full-stroke load monitoring function

Abstract

The invention relates to an electric cylinder, in particular to an electric cylinder with a full-stroke load monitoring function, which comprises a driving assembly, a push rod, a thrust output device, a force sensor, a sensor cable, a cylinder barrel, a first protective tube and a second protective tube, one end of the push rod is a driving end, the other end of the push rod is an output end, the driving end is arranged in the cylinder barrel, and the second protective tube is arranged in the cylinder barrel. The driving assembly drives the push rod to move front and back, the thrust output device is connected to the output end of the push rod, the force sensor is connected between the thrust output device and the output end of the push rod, the sensor cable is connected with the force sensor, the sensor cable is telescopic, and the force sensor is connected with the thrust output device. The extensible length of the sensor cable is larger than or equal to the maximum stroke of the push rod, the second protection pipe is suitable for moving relative to the first protection pipe, and the sensor cable is arranged in the second protection pipe. The electric cylinder with the full-stroke load monitoring function is simple and compact in structure and more accurate in output force monitoring.

Description

Technical Field

[0001] The invention relates to an electric cylinder, in particular to an electric cylinder with a full-stroke load monitoring function. Background Art

[0002] The electric cylinder is an electric actuator that is driven by a motor to drive the lead screw nut to rotate and converts rotary motion into linear motion through limited rotation. Compared with hydraulic cylinders, electric cylinders are controlled by electrical signals, have good controllability, and can monitor parameters such as position, speed, and torque in real time. However, electric cylinders generally monitor the current of the drive motor and then indirectly calculate the output force and other parameters of the electric cylinder. Due to the efficiency loss inside the electric cylinder structure, the torque calculated based on the current and then the output force of the electric cylinder are calculated, which cannot directly reflect the actual load of the electric cylinder; moreover, when the electric cylinder has structural stagnation and the running resistance is too large, resulting in the abnormally large current detected by the motor, the output force of the electric cylinder calculated by monitoring the current will be abnormal. Therefore, an electric cylinder with more accurate output force monitoring is needed. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide an electric cylinder with a simple and compact structure and more accurate monitoring of output force.

[0004] In order to solve the above technical problems, this application provides the following technical solutions:

[0005] The present invention provides an electric cylinder with a full-stroke load monitoring function, comprising a driving component, a push rod, a thrust output device, a force sensor, a sensor cable, and a cylinder barrel. One end of the push rod is a driving end and the other end is an output end. The driving end is arranged in the cylinder barrel. The driving component is connected to the driving end of the push rod. The driving component drives the push rod to move forward and backward. The thrust output device is connected to the output end of the push rod. The force sensor is connected between the thrust output device and the output end of the push rod. The sensor cable is connected to the force sensor. The sensor cable is retractable, and the extendable length of the sensor cable is greater than or equal to the maximum stroke of the push rod.

[0006] The sensor cable comprises two straight segments and a spiral segment clamped between the two straight segments. The spiral segment is extended along the axis when subjected to tension and automatically shortened to a collapsed length when not subjected to tension.

[0007] Furthermore, it also includes a first protective tube and a second protective tube which are coaxially arranged, the first protective tube is fixed in position, one end of the second protective tube is connected to the push rod and is synchronized with the push rod, the other end of the second protective tube extends into the inner cavity of the first protective tube, the second protective tube is suitable for axial movement relative to the first protective tube, the sensor cable is arranged in the second protective tube, and the end of the sensor cable away from the force sensor is connected to the first protective tube.

[0008] Furthermore, a guide sleeve is provided on the inner wall of the first protection tube, and the second protection tube is connected to the guide sleeve.

[0009] Furthermore, the first protection tube and the cylinder are parallel to each other, and the first protection tube is connected to the outer wall of the cylinder.

[0010] Furthermore, the force sensor is connected to the output end of the push rod via a screw, and the thrust output device is connected to the force sensor via a threaded connection.

[0011] Furthermore, the force sensor adopts a hole-spoke structure and an end-face wire outlet form.

[0012] Furthermore, the thrust output device is a ball head.

[0013] Furthermore, the drive assembly includes a servo motor, a reducer, a transmission device, and a screw pair. The screw pair is located in the cylinder. The output shaft of the servo motor is connected to the input end of the reducer, the output end of the reducer is connected to the input end of the transmission device, the output end of the transmission device is connected to the screw in the screw pair, the nut in the screw pair is connected to the push rod, and the nut and the push rod are in contact with the inner wall of the cylinder so that the nut and the push rod are suitable for axial movement.

[0014] Furthermore, the inner wall of the cylinder is provided with an inner keyway, and the push rod and the nut of the lead screw pair are connected to the cylinder key.

[0015] Compared with the prior art, the electric cylinder with full-stroke load monitoring function of the present invention has at least the following beneficial effects:

[0016] The present invention provides an electric cylinder with a full-stroke load monitoring function. Since a force sensor is connected between a thrust output device and an output end of a push rod, a sensor cable is connected to the force sensor, and the sensor cable is retractable, direct measurement of the output force of the electric cylinder can be achieved through the force sensor, the load measurement is more accurate, and the structure is simple and compact.

[0017] The electric cylinder with full-stroke load monitoring function of the present invention will be further described below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the electric cylinder with full-stroke load monitoring function of the present invention;

[0019] Figure 2 The schematic diagram of the structure of the sensor cable in the electric cylinder with full-stroke load monitoring function of the present invention. DETAILED DESCRIPTION

[0020] like Figure 1 As shown, the present invention is an electric cylinder with a full-stroke load monitoring function, including a driving component 01, a push rod 02, a thrust output device 03, a force sensor 04, a sensor cable 41, and a cylinder barrel 05. One end of the push rod 02 is a driving end and the other end is an output end. The driving end is arranged in the cylinder barrel 05. The driving component 01 is connected to the driving end of the push rod 02. The driving component 01 drives the push rod 02 to move forward and backward so that the push rod 02 extends out of the cylinder barrel 05 or retracts into the cylinder barrel 05. The thrust output device 03 is connected to the output end of the push rod 02. The thrust output device 03 is used to output force. The force sensor 04 is connected between the thrust output device 03 and the output end of the push rod 02. The sensor cable 41 is connected to the force sensor 04. The sensor cable 41 is retractable. The extendible length of the sensor cable 41 is greater than or equal to the maximum stroke of the push rod 02. When the electric cylinder with full-stroke load monitoring function of the present invention is working, the driving component 01 drives the push rod 02 to move relative to the cylinder barrel 05, drives the thrust output device 03 and the force sensor 04 to move, and outputs force to the outside through the thrust output device 03. The force sensor 04 is used to directly measure the load of the driving component 01 acting on the thrust output device 03. In the electric cylinder with full-stroke load monitoring function of the present invention, since the force sensor 04 is connected between the thrust output device 03 and the output end of the push rod 02, the sensor cable 41 is connected to the force sensor 04, and the sensor cable 41 is retractable, the output force of the electric cylinder can be directly measured through the force sensor 04, the load measurement is more accurate, and the structure is simple and compact.

[0021] Alternatively, if Figure 1 , Figure 2 As shown, the sensor cable 41 includes two straight segments and a spiral segment clamped between the two straight segments. The spiral segment extends along the axis when subjected to tension, and automatically shortens to a collapsed length when not subjected to tension. The extendable length of the spiral segment is greater than or equal to the maximum stroke of the push rod 02. During the synchronous movement of the force sensor 04 and the push rod 02, the sensor cable 41 can be freely extended and retracted within the full stroke range of the push rod 02.

[0022] Optionally, it also includes a first protective tube 42 and a second protective tube 43 that are coaxially arranged. The first protective tube 42 is fixed in position. One end of the second protective tube 43 is connected to the push rod 02 and synchronized with the push rod 02. The other end of the second protective tube 43 extends into the inner cavity of the first protective tube 42. The second protective tube 43 is suitable for axial movement relative to the first protective tube 42. The sensor cable 41 is arranged in the second protective tube 43, and the end of the sensor cable 41 away from the force sensor 04 is connected to the first protective tube 42. When the driving component 01 drives the push rod 02 to move, it drives the second protective tube 43 to move synchronously. By setting the first protective tube 42 and the second protective tube 43, the spiral section is extended and retracted inside the second protective tube 43, which protects the sensor cable 41 from damage and enables the sensor cable 41 to freely retract and retract.

[0023] Optionally, a guide sleeve is provided on the inner wall of the first protection tube 42 , and the second protection tube 43 is connected inside the guide sleeve. The guide sleeve is used to support the second protection tube 43 and facilitate the movement of the second protection tube 43 relative to the first protection tube 42 .

[0024] Optionally, the first protection tube 42 is parallel to the cylinder 05, the first protection tube 42 is arranged outside the cylinder 05, and the first protection tube 42 is connected to the outer wall of the cylinder 05. Specifically, the outer wall of the cylinder 05 is provided with two support blocks 51 and 52, the two ends of the first protection tube 42 are respectively connected to one support block, the support block 51 is provided with a center hole, and the plug of the sensor cable 41 is arranged in the center hole.

[0025] Optionally, the force sensor 04 is connected to the output end of the push rod 02 via a screw, and the thrust output device 03 is connected to the force sensor 04 via a threaded connection, so as to facilitate installation and disassembly of the thrust output device 03 and the force sensor 04 .

[0026] Optionally, the force sensor 04 adopts a hole-spoke structure and an end-face outlet form, which can be easily installed on the push rod 02.

[0027] Optionally, the thrust output device 03 is a ball head.

[0028] Optionally, the drive component 01 includes a servo motor 11, a reducer 12, a transmission device 13, and a screw pair 14. The output shaft of the servo motor 11 is connected to the input end of the reducer 12, the output end of the reducer 12 is connected to the input end of the transmission device 13, the output end of the transmission device 13 is connected to the screw in the screw pair 14, the nut in the screw pair 14 is connected to the push rod 02, the servo motor 11 is the power source of the electric cylinder, the servo motor 11 drives the reducer 12 and the gear pair in the transmission device 13 to rotate, and the gear pair then drives the screw in the screw pair 14 to rotate, the nut of the screw pair 14 is connected to the push rod 02, and an internal keyway is provided on the inner hole of the cylinder barrel 05 to limit the rotation of the push rod 02 and the nut of the screw pair 14 fixed thereto, thereby realizing the conversion of the screw rotational motion of the screw pair into the linear motion of the nut, and the nut drives the push rod 02 to make a linear motion, thereby realizing the extension and retraction action of the electric cylinder.

[0029] The embodiments described above are merely descriptions of preferred implementation modes of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. An electric cylinder with full-stroke load monitoring function, characterized in that: The invention comprises a driving component (01), a push rod (02), a thrust output device (03), a force sensor (04), a sensor cable (41), and a cylinder (05). One end of the push rod (02) is a driving end and the other end is an output end. The driving end is arranged in the cylinder (05). The driving component (01) is connected to the driving end of the push rod (02). The driving component (01) drives the push rod (02) to move forward and backward. The thrust output device (03) is connected to the output end of the push rod (02). The force sensor (04) is connected between the thrust output device (03) and the output end of the push rod (02). The sensor cable (41) is connected to the force sensor (04). The sensor cable (41) is retractable. The extendable length of the sensor cable (41) is greater than or equal to the maximum stroke of the push rod (02).

2. The electric cylinder with full-stroke load monitoring function according to claim 1 is characterized in that: The sensor cable (41) comprises two straight segments and a spiral segment clamped between the two straight segments. The spiral segment stretches along the axis when subjected to tension and automatically shortens to a collapsed length when not subjected to tension.

3. The electric cylinder with full-stroke load monitoring function according to claim 2 is characterized in that: It also includes a first protective tube (42) and a second protective tube (43) which are coaxially arranged. The first protective tube (42) is fixed in position. One end of the second protective tube (43) is connected to the push rod (02) and is synchronized with the push rod (02). The other end of the second protective tube (43) extends into the inner cavity of the first protective tube (42). The second protective tube (43) is suitable for axial movement relative to the first protective tube (42). The sensor cable (41) is arranged in the second protective tube (43). The end of the sensor cable (41) away from the force sensor (04) is connected to the first protective tube (42).

4. The electric cylinder with full-stroke load monitoring function according to claim 3 is characterized in that: The inner wall of the first protection tube (42) is provided with a guide sleeve, and the second protection tube (43) is connected inside the guide sleeve.

5. The electric cylinder with full-stroke load monitoring function according to claim 4 is characterized in that: The first protection tube (42) and the cylinder barrel (05) are parallel to each other, and the first protection tube (42) is connected to the outer wall of the cylinder barrel (05).

6. The electric cylinder with full-stroke load monitoring function according to claim 1, characterized in that: The force sensor (04) is connected to the output end of the push rod (02) via a screw, and the thrust output device (03) is connected to the force sensor (04) via a threaded connection.

7. The electric cylinder with full-stroke load monitoring function according to claim 6, characterized in that: The force sensor (04) adopts a hole-spoke structure and an end-face wire outlet form.

8. The electric cylinder with full-stroke load monitoring function according to claim 1, characterized in that: The thrust output device (03) is a ball head.

9. The electric cylinder with full-stroke load monitoring function according to claim 1, characterized in that: The driving assembly (01) comprises a servo motor (11), a reducer (12), a transmission device (13), and a screw pair (14); the screw pair (14) is located in the cylinder (05); the output shaft of the servo motor (11) is connected to the input end of the reducer (12); the output end of the reducer (12) is connected to the input end of the transmission device (13); the output end of the transmission device (13) is connected to the screw in the screw pair (14); the nut in the screw pair (14) is connected to the push rod (02); the nut and the push rod (02) are in contact with the inner wall of the cylinder (05) so that the nut and the push rod (02) are suitable for axial movement.

10. The electric cylinder with full-stroke load monitoring function according to claim 9, characterized in that: The inner wall of the cylinder (05) is provided with an inner keyway, and the push rod (02) and the nut of the screw pair (14) are key-connected with the cylinder (05).

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