Integrated electric cylinder

Abstract

The utility model relates to the technical field of electric cylinders, in particular to an integrated electric cylinder which comprises a cylinder body, a power driving unit, a supporting and detecting unit and a transmission unit are arranged in the cylinder body, the transmission unit comprises a reverse planetary roller lead screw, the output end of the reverse planetary roller lead screw is driven by the driving unit to do linear reciprocating motion, and the output end of the reverse planetary roller lead screw is driven by the supporting and detecting unit to do linear reciprocating motion. The supporting and detecting unit comprises a displacement sensor and a temperature sensor, the displacement sensor is installed in the reverse planetary roller screw and used for monitoring the position of the reverse planetary roller screw doing linear reciprocating motion, and the temperature sensor is arranged on the outer surface of the cylinder body and the connecting face between the reverse planetary roller screw and the driving unit and used for monitoring the position of the reverse planetary roller screw doing linear reciprocating motion. According to the utility model, the graphene distributed sensor arrays are arranged on the outer surface of the cylinder body of the electric cylinder and the connecting surface between the reverse planetary roller screw and the driving unit, so that the temperature of the whole outer surface and the interior of the electric cylinder can be comprehensively monitored.

Description

Technical Field

[0001] The utility model relates to the technical field of electric cylinders, in particular to an integrated electric cylinder. Background Art

[0002] Electric cylinders are products designed for continuous motion, low to high loads (usually high speeds), and can be cycled many times over their service life. These products have extremely high positioning accuracy and controllability, and can achieve precise motion control under loads from several kilograms to 50 tons.

[0003] In terms of size, electric cylinders are more compact. Ewellix's electric cylinders use precision ball or roller screws to replace hydraulic systems, such as the planetary roller screw linear actuator with publication number CN116722696A, which is driven by an external motor and gearbox. They are lightweight and directly connected to the motor that drives the actuator. The electromechanical system no longer requires bulky pumps, accumulators, oil tanks and pipes, nor does it require the use of hydraulic oil. It has the advantages of being safer and more environmentally friendly, and can eliminate the risks of fire, pollution or personal injury associated with leaks and spills.

[0004] Existing electric cylinders such as publication number CN 111130263 B, an integrated electric cylinder based on a reverse planetary roller screw, are provided with a magnetostrictive displacement sensor including a sensing rod and a sensing block, the sensing rod is connected to the end cover, the sensing block is connected to the screw, and the sensing block makes a linear reciprocating motion with the screw to realize the feedback of the absolute position of the screw, thereby realizing the position closed-loop control of the integrated electric cylinder; the feedback position information is the absolute position parameter of the screw, compared with the traditional absolute encoder feedback, it avoids the introduction of errors in the transmission links such as the screw drive and the key connection, and realizes high-precision position closed-loop control, but there is no monitoring feedback for the temperature change of the electric cylinder, or the feedback temperature surface is narrow and the monitoring surface is not wide enough. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides an integrated electric cylinder, so that a graphene distributed sensor array is arranged on the outer surface of the electric cylinder body and on the connecting surface between the reverse planetary roller screw and the drive unit, so as to comprehensively monitor the entire outer surface and internal temperature of the electric cylinder.

[0006] The utility model is realized by the following technical solutions:

[0007] An integrated electric cylinder comprises a cylinder body, wherein a power drive unit, a support and detection unit and a transmission unit are arranged inside the cylinder body, the transmission unit comprises a reverse planetary roller screw, the output end of the reverse planetary roller screw performs linear reciprocating motion under the drive of the drive unit, the support and detection unit comprises a displacement sensor and a temperature sensor, the displacement sensor is installed in the reverse planetary roller screw to monitor the position of the reverse planetary roller screw performing linear reciprocating motion, and the temperature sensor is arranged on the outer surface of the cylinder body and the connecting surface between the reverse planetary roller screw and the drive unit, and is used to monitor the temperature of the electric cylinder.

[0008] Further preferably, the cylinder body comprises an outer shell, and a front end cover and a rear end cover are arranged at both ends of the outer shell.

[0009] Further preferably, the reversing planetary roller screw includes a nut, a screw, a roller and a push rod, one end of the push rod is installed in the housing, the telescopic end of the push rod extends out of the housing, the screw, roller and nut are sequentially sleeved on the outside of the push rod in the housing, and the nut is connected to the frameless motor.

[0010] Further preferably, the power drive unit includes a frameless motor, the frameless motor includes a stator winding and a rotor permanent magnet, the stator winding is pressed onto the inner wall of the housing, and the rotor permanent magnet is connected between the nut and the stator winding.

[0011] Further preferably, the temperature sensor includes temperature sensor 1 and temperature sensor 2, the temperature sensor 1 is arranged on the outer surface of the shell, and the temperature sensor 2 is attached to the outer surface of the nut.

[0012] Further preferably, the temperature sensor 1 and the temperature sensor 2 are graphene distributed sensor arrays.

[0013] Further preferably, the support and detection unit also includes a bearing and a bushing, the bearing sleeve is arranged in the outer shell near one end of the front end cover, the bushing sleeve is arranged in the front end cover, the bearing adopts a four-point angular contact ball bearing, and the bushing adopts a brass sliding bushing.

[0014] Further preferably, the support and detection unit also includes a motor encoder unit sleeved in the rear end cover and a force sensing sensor attached to the outer end surface of the rear end cover, and the motor encoder unit includes an integrated rotary bearing and a rotary encoder.

[0015] Beneficial effects of the utility model:

[0016] 1) The utility model is an integrated electric cylinder, which solves the problem of complex structure of existing electric cylinders by selecting new components and materials, improves the power density of the electric cylinder, realizes the control of three modes of speed, position and torque of the electric cylinder, and can also monitor the operating status of key components of the electric cylinder through temperature changes.

[0017] 2) The utility model provides a graphene distributed sensor array on the outer surface of the cylinder body and the connection surface between the reverse planetary roller screw and the drive unit to comprehensively monitor the entire outer surface and internal temperature of the electric cylinder to improve detection accuracy.

[0018] 3) The bearing near the front end cover of the utility model adopts a four-point angular contact ball bearing, and the motor encoder unit in the rear end cover adopts an integrated rotary bearing and rotary encoder, which simplifies the structure and improves the power density of the electric cylinder.

[0019] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention, but do not constitute a limitation to the present invention. In the accompanying drawings:

[0021] Figure 1 The utility model is a structural schematic diagram of an integrated electric cylinder.

[0022] 11-housing, 12-front cover, 13-rear cover, 21-rotating seal ring, 22-dustproof seal ring, 23-O-ring, 311-stator winding, 312-rotor permanent magnet, 32-drive controller, 33-electromagnetic brake, 41-bearing, 42-shaft bushing, 43-motor encoder unit, 44-displacement sensor, 45-force sensing sensor, 46-temperature sensor 1, 47-temperature sensor 2, 48-conductive slip ring, 51-nut, 52-screw, 53-roller, 54-retaining ring, 55-push rod. DETAILED DESCRIPTION

[0023] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0024] refer to Figure 1An integrated electric cylinder is divided into functional units, and is composed of a cylinder body, a power drive unit, a support and detection unit, a transmission unit and other unit components. The cylinder body includes a housing 11, a front cover 12, and a rear cover 13; the front cover 12 and the rear cover 13 are arranged at both ends of the housing 11, and the power drive unit includes a frameless motor, a drive controller 32, and an electromagnetic brake 33; the drive controller 32 is connected to the frameless motor, and the electromagnetic brake 33 is used as a reducer between the drive controller 32 and the frameless motor to control the speed. The drive controller 32 and the electromagnetic brake 33 are installed in the rear cover 13. The integrated electric cylinder also includes a sealing unit, and the sealing unit includes a rotating sealing ring 21, a dustproof sealing ring 22, an O-ring 23, etc. to seal the equipment.

[0025] The transmission unit is a reverse planetary roller screw, also called a reversing planetary roller screw, which is a prior art and is mainly composed of a nut 51, a screw 52, ​​a roller 53, a retaining ring 54, and a push rod 55. The push rod 55 is in the housing 11 and its telescopic end extends out of the housing 11. The roller 53 is fixedly connected to the screw 52, ​​the roller 53 is threadedly connected to the nut 51, and the screw 52 is threadedly connected to the roller 53. The reverse planetary roller screw is a roller 53 connected to a screw 52, ​​and the screw 52 is driven by a nut 51 to make a linear motion. The nut 51 is connected to the frameless motor to provide a driving force for it. The frameless motor includes a stator winding 311 and a rotor permanent magnet 312. The stator winding 311 is pressed onto the inner wall of the housing 11. The housing 11 and the stator winding 311 are connected by a key to limit the rotational freedom of the stator winding 311, thereby realizing the fixed installation of the stator winding 311. The rotor permanent magnet 312 is connected between the nut 51 and the stator winding 311. The other specific structures and working principles of the reverse planetary roller 53 screw 52 are not repeated here. For details, see the prior art in the background technology.

[0026] The support and detection unit includes a bearing 41, a bushing 42, a motor encoder unit 43, a displacement sensor 44, a force sensing sensor 45 and a temperature sensor. The bearing 41 is sleeved in the outer shell 11 near one end of the front end cover 12. The outer ring of the bearing 41 is interference fit with the inner surface of the outer shell 11, and the inner ring of the bearing 41 is interference fit with the outer surface of the nut 51. The bushing 42 is sleeved in the front end cover 12, the motor encoder unit 43 is sleeved in the rear end cover 13, one end of the displacement sensor 44 is installed in the rear end cover 13, the force sensing sensor 45 is attached to the outer end surface of the rear end cover 13, and there are two temperature sensors, including temperature sensor 1 46 and temperature sensor 2 47. Temperature sensor 1 46 is arranged on the outer surface of the outer shell 11, and temperature sensor 2 47 is attached to the entire outer surface of the nut 51. The material of the nut 51 is preferably a magnetic conductive material. The wire of the temperature sensor 2 47 attached to the outer surface of the nut 51 is connected to the outside of the electric cylinder through a conductive slip ring 48. The rotor permanent magnet 312 is attached to the temperature sensor 2 47 on the outer surface of the nut 51. The rotor permanent magnet 312, the nut 51, and the temperature sensor 2 47 together constitute the rotor of the frameless motor.

[0027] Bearing 41 is a four-point angular contact ball bearing; the four-point contact ball bearing is a prior art and is a separable structure. A single bearing can replace the front or back combination angular contact ball bearing. It can bear radial load and bidirectional axial load, and can limit the axial displacement in two directions, but it occupies less axial space than the double-row angular contact ball bearing of the current specification. Compared with other ball bearings, the four-point contact ball bearing has a smaller axial clearance and a higher limit speed when the radial clearance is the same. Because it is a double semi-inner ring (or outer ring), the number of balls is increased, and it has a greater load-bearing capacity.

[0028] The bushing 42 is a brass sliding bushing; the motor encoder unit 43 is an integrated rotary bearing and a rotary encoder; such as the SKF bearing 41BMB-6202 / 032S2 / EA002A imported from Sweden; the displacement sensor 44 is a magnetostrictive displacement sensor; the force sensing sensor 45, the temperature sensor 1 46 and the temperature sensor 2 47 are graphene flexible film sensors, which are prior art and are also called graphene distributed sensor arrays. On the basis of the preparation of graphene unit devices, multiple physical quantity sensors such as pressure, strain, temperature and humidity are integrated on a flexible substrate; array graphics are realized by combining photolithography, etching and laser ablation; metal electrode leads are prepared by screen printing, inkjet printing and other methods to realize the preparation of multiple physical quantity graphene distributed sensor arrays.

[0029] In summary, although the present invention has been disclosed as above in terms of preferred embodiments, the above preferred embodiments are not intended to limit the present invention. A person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. An integrated electric cylinder, characterized in that: The invention comprises a cylinder body, wherein a power drive unit, a support and detection unit and a transmission unit are arranged inside the cylinder body, wherein the transmission unit comprises a reverse planetary roller screw, wherein the output end of the reverse planetary roller screw performs linear reciprocating motion under the drive of the drive unit, wherein the support and detection unit comprises a displacement sensor (44) and a temperature sensor, wherein the displacement sensor (44) is installed inside the reverse planetary roller screw to monitor the position of the reverse planetary roller screw performing linear reciprocating motion, and wherein the temperature sensor is arranged on the outer surface of the cylinder body and on the connection surface between the reverse planetary roller screw and the drive unit to monitor the temperature of the electric cylinder.

2. The integrated electric cylinder according to claim 1, characterized in that: The cylinder body comprises an outer shell (11), and a front end cover (12) and a rear end cover (13) are arranged at both ends of the outer shell (11).

3. The integrated electric cylinder according to claim 2, characterized in that: The reversing planetary roller screw comprises a nut (51), a screw (52), a roller (53) and a push rod (55), one end of the push rod (55) is installed in the housing (11), the telescopic end of the push rod (55) extends out of the housing (11), and the screw (52), the roller (53) and the nut (51) are sequentially sleeved outside the push rod (55) in the housing (11).

4. The integrated electric cylinder according to claim 3, characterized in that: The power drive unit comprises a frameless motor, the frameless motor comprises a stator winding (311) and a rotor permanent magnet (312), the stator winding (311) is pressed onto the inner wall of the housing (11), and the rotor permanent magnet (312) is connected between the nut (51) and the stator winding (311).

5. The integrated electric cylinder according to claim 3, characterized in that: The temperature sensor comprises a temperature sensor 1 (46) and a temperature sensor 2 (47), wherein the temperature sensor 1 (46) is arranged on the outer surface of the housing (11), and the temperature sensor 2 (47) is attached to the outer surface of the nut (51).

6. The integrated electric cylinder according to claim 5, characterized in that: The temperature sensor 1 (46) and the temperature sensor 2 (47) are both graphene distributed sensor arrays.

7. The integrated electric cylinder according to claim 2, characterized in that: The support and detection unit also includes a bearing (41) and a bushing (42), wherein the bearing (41) is sleeved in the housing (11) near one end of the front end cover (12), and the bushing (42) is sleeved in the front end cover (12). The bearing (41) is a four-point angular contact ball bearing, and the bushing (42) is a brass sliding bushing.

8. The integrated electric cylinder according to claim 2, characterized in that: The support and detection unit also includes a motor encoder unit (43) sleeved in the rear end cover (13) and a force sensing sensor (45) attached to the outer end surface of the rear end cover (13), wherein the motor encoder unit (43) includes an integrated rotary bearing and a rotary encoder.

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