Multi-turn angular displacement potentiometer based on conductive plastic resistor body

Abstract

The invention discloses a multi-turn angular displacement potentiometer based on a conductive plastic resistor body, which belongs to the technical field of angular displacement potentiometer production, and comprises a shell, a driving shaft, a resistor body, a collector ring, an electric brush assembly, connecting guide rods, end plates, a screw rod, an annular rack and a transmission gear, the connecting guide rod is connected with the driving shaft, the lead screw is connected with the two end plates through bearings, the lead screw penetrates through corresponding through holes in the driving shaft, one end of the lead screw is sleeved with the transmission gear, and the transmission gear is connected with the annular rack in a meshed mode. The nut is arranged in the central through hole of the electric brush seat, is sleeved outside the lead screw and is in threaded connection with the lead screw; and the working tape on the resistor body is a multi-circle spiral working tape positioned on the same plane. The multi-turn angular displacement detection function or the different voltage output function can be achieved, machining is convenient, precision is high, and application is convenient.

Description

Technical Field

[0001] The invention belongs to the technical field of production of angular displacement potentiometers (sensors), and specifically relates to a multi-turn angular displacement potentiometer, and in particular to a multi-turn angular displacement potentiometer based on a conductive plastic resistor. Background Art

[0002] The electrical stroke of the angular displacement potentiometer based on conductive plastic resistor is generally less than 360°, that is, a working band with an angle less than 360° is set on one side surface of the resistor and the brush is in contact with the working band. This angular displacement potentiometer cannot be used in applications where an angular displacement exceeding 360° or voltage control exceeding 360° is detected.

[0003] A multi-turn angular displacement potentiometer is an angular displacement potentiometer that can detect an angular displacement of more than 360° or a voltage control of more than 360°. A conventional multi-turn angular displacement potentiometer generally uses a resistor body with a cylindrical spiral working band, and its brush is generally a cantilever brush, and its contact portion is generally bent at a certain angle to facilitate elastic contact and sliding with the working band of the resistor body. This conventional multi-turn angular displacement potentiometer has the following defects: First of all, the resistor body of the traditional multi-turn angular displacement potentiometer is a cylinder, and the working belt is arranged on the inner wall of the cylinder. This structure makes the processing of the resistor body difficult. Generally, the resistor body is processed by first processing the strip-shaped resistor body and then winding the strip-shaped resistor body into a cylindrical spiral shape. It is very difficult to control the distance between the entire working belt and the center line of the cylinder to be equal in this way. There is a problem of different contact forces when the brush contacts and slides with the working belt, which will cause the contact resistance to change, and ultimately lead to a decrease in the angular displacement detection accuracy or voltage control accuracy, which limits its application.

[0004] Secondly, the brush of the traditional multi-turn angular displacement potentiometer is a cantilever brush, and the end of the brush wire that contacts the resistor is the cantilever end, and the other end connected to the brush holder needs to provide support. The cantilever brush specifically includes an upward brush and a downward brush. No matter which cantilever brush is used, the following defects exist: in order to ensure that the brush contacts are in reliable contact and not detached, a large amount of compression and pressure are reserved in the design. However, due to the cantilever structure, it is only supported at a single point, and the contact is far away from the support point. Its stability is relatively poor and contact tremor is prone to occur. Especially when used in complex working conditions such as vibration, it is easy to cause the potentiometer to have poor applicability, such as large and / or large changes in contact resistance, large and / or large changes in sliding noise, large return error, short elastic life, etc., which ultimately lead to low detection accuracy or voltage control accuracy and short service life of the potentiometer. Summary of the invention

[0005] The object of the present invention is to provide a multi-turn angular displacement potentiometer based on a conductive plastic resistor which is easy to process and has high detection accuracy or voltage control accuracy in order to solve the above problems.

[0006] The present invention achieves the above-mentioned purpose through the following technical solutions: A multi-turn angular displacement potentiometer based on a conductive plastic resistor, comprising a housing, a drive shaft, a resistor, a collector ring and a brush assembly, wherein the drive shaft passes through a corresponding through hole on the housing and is connected through a bearing, the annular resistor, the annular collector ring and the brush assembly are respectively installed in the housing, the drive shaft passes through a central through hole of the resistor and a central through hole of the collector ring, a working belt is provided on one side surface of the resistor, a conductive belt is provided on one side surface of the collector ring, the resistor and the collector ring are respectively close to the inner walls on opposite sides of the housing, the multi-turn angular displacement potentiometer based on a conductive plastic resistor also comprises a connecting guide rod, an end plate, a lead screw, an annular rack and a transmission gear disposed in the housing and between the resistor and the collector ring, the two ends of the two parallel connecting guide rods are respectively connected to the end plates, the connecting guide rod and the drive shaft are perpendicular to each other and the middle sections of the two connecting guide rods are connected to the middle section of the drive shaft, the lead screw and the The connecting guide rods are parallel to each other and are located between the two connecting guide rods. The positions near the two ends of the lead screw are connected to the two end plates through bearings respectively. The middle section of the lead screw passes through the corresponding through holes on the drive shaft and does not contact each other. The annular transmission gear is sleeved on the outside of one end of the lead screw through its own center through hole and is meshed with the annular ring rack installed on the inner wall of the shell. The center line of the transmission gear is perpendicular to the center line of the ring rack and is parallel to the center line of the lead screw. The brush assembly includes an insulating brush holder, a conductive brush and a nut. The brush is installed on the brush holder and is in contact with the working belt on the resistor and the conductive belt on the collector ring at the same time. The nut is fixedly installed in the center through hole of the brush holder and is sleeved on the outside of the lead screw and is threadedly connected. Two guide through holes are provided on the brush holder and the two connecting guide rods pass through the two guide through holes respectively. The working belt on the resistor is a multi-turn spiral working belt located in the same plane.

[0007] Preferably, in order to facilitate the connection between the brush and the brush holder and improve the service life and detection accuracy of the brush, the elliptical brush formed by multiple annular closed brush wires arranged side by side is installed on the outer wall of the elliptical or elliptical brush holder, the two ends of the short axis of the brush are respectively connected to the two ends of the short axis of the brush holder, and the two ends of the long axis of the brush are respectively separated from the two ends of the long axis of the brush holder. The two guide through holes are respectively arranged on the brush holder near the two ends of the long axis, and the two ends of the long axis of the brush are bent to form a brush contact part and the two brush contact parts are respectively in contact with the working band on the resistor and the conductive band on the collector ring. The above-mentioned elliptical shape is a shape close to an elliptical shape. More specifically, the shape includes a long axis and a short axis perpendicular to each other, the two ends of the long axis are convex, and the outer surfaces of the two ends of the long axis are transitioned by arc surfaces or inclined surfaces. This is a conventional definition of a elliptical shape.

[0008] Preferably, in order to achieve a reliable connection between the nut and the brush holder and ensure that the brush signal is not transmitted to components such as the screw rod through the brush holder, and at the same time to stably and reliably connect the brush and the brush holder, the brush holder is a plastic holder, the nut and the brush holder are integrally insert-molded, the two ends of the short axis of the brush are respectively placed on the outside of the two ends of the short axis of the brush holder, and the two metal plates are respectively located outside the two ends of the short axis of the brush and are respectively connected to the outer walls of the two ends of the short axis of the brush holder through connecting screws.

[0009] Preferably, in order to more stably and reliably connect the brush and the brush holder, a through hole is provided on the metal plate at a position corresponding to the brush, and solder is provided in the through hole and in the surrounding area to achieve a fixed connection between the brush and the corresponding metal plate, and the two connecting screws are respectively located on both sides of the solder.

[0010] Preferably, in order to further realize the anti-rotation connection function between the nut and the brush holder, the nut is provided with outwardly protruding nut bosses on two opposite sides in one direction, and the nut bosses are provided with mounting holes, and the nut is provided with outwardly protruding positioning bumps on two opposite sides in the other direction, and the positioning bumps are embedded in the brush holder.

[0011] Preferably, in order to eliminate the influence of the gap caused by the threaded connection between the brush holder and the lead screw and improve the detection accuracy of the potentiometer, the multi-turn angular displacement potentiometer based on the conductive plastic resistor also includes an anti-backlash seat, a screw hole is provided in the middle part of the anti-backlash seat and the lead screw passes through the screw hole and is threadedly connected, two guide through holes are provided on the anti-backlash seat and the two connecting guide rods pass through the two guide through holes respectively, a mounting groove is provided on the side surface of the brush holder close to the anti-backlash seat at a position corresponding to the nut boss and the two nut bosses are respectively placed in the corresponding mounting grooves, one end of two parallel anti-backlash springs are respectively connected to the mounting holes on the two nut bosses and placed in the corresponding mounting grooves, and the other ends of the two anti-backlash springs are respectively connected to the anti-backlash seat.

[0012] Preferably, in order to make the brush contact portion have both good bending strength and detection accuracy, the bending angle of the two brush contact portions of the brush is 60°-120°.

[0013] Preferably, in order to facilitate better cooperation between the driving shaft and the connecting guide rod and the screw rod, the outer diameter of the middle section of the driving shaft is increased to form a large diameter section, the middle sections of the two connecting guide rods respectively pass through the corresponding through holes on the large diameter section and are connected by pins, and the middle sections of the screw rod pass through the corresponding through holes on the large diameter section without contacting each other.

[0014] Preferably, to facilitate processing and assembly, the shell includes a shell seat, a shell tube and a shell cover, the two ends of the shell tube are respectively connected to the shell seat and the shell cover by screws, the resistor is mounted on the inner wall of the shell seat, the annular rack is mounted on the inner wall of the shell tube and close to the shell cover, the collector ring is mounted on the inner wall of the shell cover, the drive shaft passes through the corresponding through hole on the shell cover and one end thereof is connected to the shell seat, the two ends of the working band on the resistor are respectively connected to the inner end of the power lead, the conductive band on the collector ring is connected to the inner end of the signal lead, the outer end of the power lead and the outer end of the signal lead respectively pass through the corresponding through holes on the shell tube and are placed outside the shell.

[0015] Preferably, in order to eliminate the effect of the clearance caused by the threaded connection between the transmission gear and the annular rack and improve the detection accuracy of the potentiometer, the transmission gear includes a first transmission gear and a second transmission gear arranged in parallel, and a torsion spring is installed between the first transmission gear and the second transmission gear to form an anti-backlash gear together.

[0016] The beneficial effects of the present invention are: The present invention sets a multi-turn spiral working belt located in the same plane as the working belt on one side surface of the resistor body, and designs a spiral rotating transmission mechanism including a connecting guide rod, an end plate, a lead screw, an annular rack, a transmission gear, a brush holder and a nut. The spiral rotating transmission mechanism can drive the brush to perform a spiral rotating motion on the working belt of the resistor body under the drive of the driving shaft, thereby realizing a multi-turn angular displacement detection function or a different voltage output function, and is convenient for accurately setting the working belt on the resistor body, which is convenient for processing. During the contact and sliding process of the brush on the working belt, the contact force is the same and the contact resistance is consistent, thereby ensuring sufficiently accurate angular displacement detection accuracy or output voltage control accuracy, and is convenient for application.

[0017] In addition, the present invention designs an elliptical brush and an elliptical or elliptical brush holder, and connects the two ends of the short axis of the brush to the two ends of the short axis of the brush holder respectively, leaving gaps between the two ends of the long axis of the brush and the two ends of the long axis of the brush holder respectively, and utilizes the brush contact parts at the two ends of the long axis of the brush to contact the working band on the resistor and the conductive band on the collector ring respectively. On the premise that the electrical signal detected on the working band of the resistor is directly transmitted to the conductive band of the collector ring through the two brush contact parts of the brush, the two symmetrical brush contact parts at the two ends of the long axis of the brush can provide a push-and-pull effect during operation in a vibrating environment, and the friction force of the brush contact part is dispersed to two fulcrums, which is not easy to shake and has small deformation. The brush contact part follows better and can eliminate hysteresis to a large extent, significantly improving the conductivity reliability and detection accuracy of the brush during the rotating contact process, with small return error, good contact stability and long service life, and can cope with various complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the main cross-sectional structure of the multi-turn angular displacement potentiometer based on the conductive plastic resistor of the present invention, wherein the brush assembly and the anti-backlash seat in the figure are the main structures; Figure 2 It is a three-dimensional structural schematic diagram of a driving shaft, a connecting guide rod, an end plate, a lead screw, a transmission gear, a brush assembly, an anti-backlash seat and an anti-backlash spring of a multi-turn angular displacement potentiometer based on a conductive plastic resistor according to the present invention; Figure 3 It is a schematic diagram of the three-dimensional structure of the brush assembly of the multi-turn angular displacement potentiometer based on the conductive plastic resistor according to the present invention; Figure 4 It is a side view structural schematic diagram of the brush assembly of the multi-turn angular displacement potentiometer based on the conductive plastic resistor according to the present invention; Figure 5 It is a three-dimensional structural schematic diagram of a nut of a brush assembly of a multi-turn angular displacement potentiometer based on a conductive plastic resistor according to the present invention; Figure 6The diagram is a top view of the structure of the resistor body of the multi-turn angular displacement potentiometer based on the conductive plastic resistor body of the present invention.

[0019] Among them, 1-housing tube, 2-housing cover, 3-annular rack, 4-first transmission gear, 5-second transmission gear, 6-end plate, 7-connecting guide rod, 8-bearing, 9-torsion spring, 10-screw rod, 11-driving shaft, 12-brush assembly, 13-pin, 14-large diameter section, 15-collector ring, 16-anti-backlash seat, 17-anti-backlash spring, 18-signal lead, 19-resistor, 20-housing seat, 21-power lead, 22-brush, 23-brush seat, 24-solder, 25-metal plate, 26-connecting screw, 27-guide through hole, 28-nut, 29-mounting groove, 30-mounting hole, 31-nut boss, 32-brush contact part, 33-positioning bump, 34-working belt. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings: like Figure 1-Figure 6As shown, the multi-turn angular displacement potentiometer based on the conductive plastic resistor of the present invention comprises a housing (refer to the housing seat 20, the housing cylinder 1 and the housing cover 2 described below), a drive shaft 11, a resistor 19, a collector ring 15, a brush assembly 12, and a connecting guide rod 7, an end plate 6, a screw rod 10, an annular rack 3 and a transmission gear (refer to the first transmission gear 4 and the second transmission gear 5 described below) disposed in the housing and located between the resistor 19 and the collector ring 15. The drive shaft 11 passes through the corresponding through hole on the housing and passes through the bearing 8 (Note: the bearings in this article are uniformly marked with 8, but The bearings 8 at different positions are not the same bearing, the same below), the annular resistor 19, the annular collector ring 15 and the brush assembly 12 are respectively installed in the housing, the drive shaft 11 passes through the central through hole of the resistor 19 and the central through hole of the collector ring 15, a working belt 34 (i.e., a conductive plastic belt) is provided on one side surface of the resistor 19, and a conductive belt (not shown in the figure) is provided on one side surface of the collector ring 15, the resistor 19 and the collector ring 15 are respectively close to the inner walls on the opposite sides of the housing, and the two ends of the two parallel connecting guide rods 7 are respectively connected to the end plate 6, and the connecting guide rods 7 is perpendicular to the driving shaft 11 and the middle sections of the two connecting guide rods 7 are connected to the middle sections of the driving shaft 11. The screw rod 10 is parallel to the connecting guide rod 7 and is located between the two connecting guide rods 7. The positions near the two ends of the screw rod 10 are connected to the two end plates 6 through bearings 8 respectively. The middle section of the screw rod 10 passes through the corresponding through holes on the driving shaft 11 and does not contact each other. The annular transmission gear is sleeved on the outside of one end of the screw rod 10 through its own central through hole and is meshed with the annular ring rack 3 installed on the inner wall of the housing. The center line of the transmission gear is aligned with the center line of the ring rack 3. The brush assembly 12 is perpendicular to each other and parallel to the center line of the lead screw 10, and includes an insulating brush holder 23, a conductive brush 22 and a nut 28. The brush 22 is mounted on the brush holder 23 and is in contact with the working belt 34 on the resistor 19 and the conductive belt on the collector ring 15 at the same time. The nut 28 is fixedly mounted in the central through hole of the brush holder 23 and is sleeved on the outside of the lead screw 10 and threadedly connected. Two guide through holes 27 are provided on the brush holder 23 and two connecting guide rods 7 pass through the two guide through holes 27 respectively. The working belt 34 on the resistor 19 is a multi-turn spiral working belt located in the same plane.

[0021] like Figure 1-Figure 6 As shown, the present invention also discloses the following more optimized specific structures: In order to facilitate the connection between the brush 22 and the brush holder 23 and to improve the service life and detection accuracy of the brush 22, an elliptical brush 22 formed by a plurality of annular closed brush wires (not separately marked in the figure, preferably using precious metal palladium-iridium alloy wire) arranged side by side is installed on the outer wall of the elliptical or elliptical brush holder 23, the two ends of the short axis of the brush 22 are respectively connected to the two ends of the short axis of the brush holder 23, and gaps are left between the two ends of the long axis of the brush 22 and the two ends of the long axis of the brush holder 23, two guide through holes 27 are respectively arranged on the brush holder 23 near the two ends of the long axis, the two ends of the long axis of the brush 22 are bent to form a brush contact portion 32, and the two brush contact portions 32 are respectively in contact with the working belt 34 on the resistor 19 and the conductive belt on the collector ring 15. The above-mentioned quasi-ellipse is a shape close to an ellipse. More specifically, the shape includes a major axis and a minor axis that are perpendicular to each other, the two ends of the major axis are convex, and the outer surfaces of the two ends of the major axis are transitioned by arc surfaces or inclined surfaces. This is a conventional definition of a quasi-ellipse.

[0022] In order to achieve a reliable connection between the nut 28 and the brush holder 23 and ensure that the electrical signal on the brush 22 is not transmitted to the screw rod 10 and other components through the brush holder 23, and at the same time to stably and reliably connect the brush 22 and the brush holder 23, the brush holder 23 is a plastic holder, and the nut 28 and the brush holder 23 are integrally insert-molded. The two ends of the short axis of the brush 22 are respectively placed on the outside of the two ends of the short axis of the brush holder 23, and two metal plates 25 (preferably palladium-iridium alloy plates or palladium-iridium alloy sheets) are respectively located outside the two ends of the short axis of the brush 22 and are respectively connected to the outer walls of the two ends of the short axis of the brush holder 23 through connecting screws 26.

[0023] In order to connect the brush 22 and the brush holder 23 more stably and reliably, a through hole (not marked in the figure) is provided at a position corresponding to the brush 22 on the metal plate 25, and solder 24 is provided in the through hole and in the surrounding area to achieve a fixed connection between the brush 22 and the corresponding metal plate 25, and two connecting screws 26 are respectively located on both sides of the solder 24.

[0024] In order to further realize the anti-rotation connection function between the nut 28 and the brush holder 23, the nut 28 is provided with outwardly protruding nut bosses 31 on opposite sides in one direction, and the nut bosses 31 are provided with mounting holes 30, and the nut 28 is provided with outwardly protruding positioning protrusions 33 on opposite sides in the other direction, and the positioning protrusions 33 are embedded in the brush holder 23.

[0025] In order to eliminate the gap effect caused by the threaded connection between the brush holder 23 and the lead screw 10 and improve the detection accuracy of the potentiometer, the multi-turn angular displacement potentiometer based on the conductive plastic resistor also includes a gap elimination seat 16, a screw hole is provided in the middle of the gap elimination seat 16, and the lead screw 10 passes through the screw hole and is threadedly connected, two guide through holes are provided on the gap elimination seat 16, and two connecting guide rods 7 pass through the two guide through holes respectively, a mounting groove 29 is provided on the side surface of the brush holder 23 close to the gap elimination seat 16 at a position corresponding to the nut boss 31, and the two nut bosses 31 are respectively placed in the corresponding mounting grooves 29, one end of two parallel gap elimination springs 17 (preferably tension springs) are respectively connected to the mounting holes 30 on the two nut bosses 31 and placed in the corresponding mounting grooves 29, and the other ends of the two gap elimination springs 17 are respectively connected to the gap elimination seat 16.

[0026] In order to make the brush contact portion 32 have both good bending strength and detection accuracy, the bending angle of the two brush contact portions 32 of the brush 22 is 60°-120°.

[0027] In order to facilitate better cooperation between the driving shaft 11 and the connecting guide rod 7 and the screw rod 10, the outer diameter of the middle section of the driving shaft 11 is increased to form a large diameter section 14, the middle sections of the two connecting guide rods 7 respectively pass through the corresponding through holes on the large diameter section 14 and are connected by pins 13, and the middle sections of the screw rod 10 pass through the corresponding through holes on the large diameter section 14 without contacting each other.

[0028] To facilitate processing and assembly, the shell includes a shell seat 20, a shell tube 1 and a shell cover 2, the two ends of the shell tube 1 are respectively connected to the shell seat 20 and the shell cover 2 by screws, the resistor 19 is installed on the inner wall of the shell seat 20, the annular rack 3 is installed on the inner wall of the shell tube 1 and close to the shell cover 2, the collector ring 15 is installed on the inner wall of the shell cover 2, the drive shaft 11 passes through the corresponding through hole on the shell cover 2 and one end thereof is connected to the shell seat 20, the two ends of the working belt 34 on the resistor 19 are respectively connected to the inner end of the power lead 21, the conductive belt on the collector ring 15 is connected to the inner end of the signal lead 18, the outer end of the power lead 21 and the outer end of the signal lead 18 respectively pass through the corresponding through holes on the shell tube 1 and are placed outside the shell.

[0029] In order to eliminate the effect of the clearance caused by the threaded connection between the transmission gear and the annular rack 3 and improve the detection accuracy of the potentiometer, the transmission gear includes a first transmission gear 4 and a second transmission gear 5 arranged in parallel, and a torsion spring 9 is installed between the first transmission gear 4 and the second transmission gear 5 to form an anti-backlash gear (the anti-backlash gear is a conventional combined gear).

[0030] Combination Figure 3-Figure 5 , the following introduces a specific preferred method for manufacturing the brush assembly 12, but the following manufacturing method is not the only method: 1. When making the mandrel, the mandrel angle should conform to the appearance characteristics of the brush 22, that is, the structure should be symmetrical. The angle design should focus on the free height of the contact after rebound. The mandrel state angle corresponding to the brush contact part 32 should be smaller than the angle of its free state, and the free state angle should be smaller than the working state angle. The mandrel state height corresponding to the brush contact part 32 should be greater than the free state height, and the free state height should be greater than the working state height. The mandrel material is made of stainless steel with high hardness and no welding characteristics. Its hardness can ensure the bending and forming of the brush 22, and its material has no welding characteristics, which is conducive to the subsequent tinning and demolding of the brush wire. In addition, the mandrel needs to be easy to make and easy to demold.

[0031] 2. The brush 22 uses precious metal palladium-iridium alloy wire with high surface hardness and weak longitudinal stiffness as the brush wire, which is beneficial to the forming of the brush 22 and maintains high wear resistance, corrosion resistance and salt spray resistance of the brush contact part 32.

[0032] 3. The brush wire is wound around the core rod. The brush wire only needs to control the tension of the brush wire and can be made into a brush wire that conforms to the shape of the core rod through dense winding.

[0033] 4. After the brush 22 is formed, a metal plate 25 made of palladium-iridium alloy is used to tin the mounting part to form solder 24. The tinning principle utilizes the capillary suction principle. When the brush wires are closely arranged, capillaries are formed between each brush wire and between the brush wire and the metal plate 25. When the solder melts, the brush wire and the metal plate 25 can be welded together through the capillaries. Since the core rod has no weldability, it can be detached after welding.

[0034] 5. Remove the head and tail of the brush wire, take off the mandrel, and the core rod can be detached to obtain an ideal brush 22.

[0035] 6. Place the brush holder 23 integrally molded with the nut 28 in the elliptical hole of the brush 22, and connect the two ends of the short axis of the brush 22 to the two ends of the short axis of the brush holder 23, respectively. Pass the connecting screws 26 through the corresponding through holes on the metal plate 25 and connect them to the corresponding screw holes on the brush holder 23. After tightening the connecting screws 26, the brush assembly 12 is obtained.

[0036] like Figure 1-Figure 6As shown, when in use, the outer end of the drive shaft 11 is connected to the driving member of the device to be detected (for detecting angular displacement), or is used for manual rotation (for outputting electrical signals of different voltages). After the drive shaft 11 starts to rotate, it drives the lead screw 10, the connecting guide rod 7, the end plate 6, the transmission gear, the brush assembly 12, the anti-backlash seat 16 and the anti-backlash spring 17 to rotate synchronously. In the process of rotating around the center line of the drive shaft 11, the transmission gear rotates around the center line of the lead screw 10 due to the engagement with the annular rack 3, thereby driving the lead screw 10 to rotate around its own center line, and the brush assembly 12 Since the anti-backlash seat 16 is threadedly matched with the lead screw 10 and cannot rotate itself, the brush assembly 12 and the anti-backlash seat 16 move axially in the lead screw 10, and finally the two brush contact parts 32 of the brush 22 respectively make spiral motion on the working belt 34 of the resistor 19 and the conductive belt of the collector ring 15, and the trajectory of its spiral motion is consistent with the spiral shape of the working belt 34 of the resistor 19, and its consistency can be achieved through reasonable adjustment of the existing technology. The brush 22 obtains the changing electrical signal and outputs it through the signal lead 18 to realize the corresponding angular displacement detection function or different voltage output function. Since the motion trajectory of the brush 22 and the working belt 34 are both constant speed spirals (the spiral is also called Archimedean spiral), the rotation angle of the drive shaft 11, that is, the electrical stroke of the potentiometer, can exceed 360° and can be infinite in theory. Under the condition of constant power supply, the larger the electrical stroke, the smaller the voltage gradient, that is, the smaller the voltage increment per angle, and in the manufacturing process, the actual voltage is easier to approach the theoretical value, that is, the higher the linearity, which is conducive to application.

[0037] The above embodiments are only preferred embodiments of the present invention and are not limitations of the technical solutions of the present invention. Any technical solution that can be implemented on the basis of the above embodiments without creative work should be deemed to fall within the scope of protection of the patent of the present invention.

Claims

1. A multi-turn angular displacement potentiometer based on a conductive plastic resistor, comprising a housing, a drive shaft, a resistor, a collector ring and a brush assembly, wherein the drive shaft passes through a corresponding through hole on the housing and is connected through a bearing, the annular resistor, the annular collector ring and the brush assembly are respectively installed in the housing, the drive shaft passes through a central through hole of the resistor and a central through hole of the collector ring, a working belt is provided on one side surface of the resistor, and a conductive belt is provided on one side surface of the collector ring, characterized in that: The resistor body and the collector ring are respectively close to the inner walls on both sides of the shell that are opposite to each other. The multi-turn angular displacement potentiometer based on the conductive plastic resistor body also includes a connecting guide rod, an end plate, a screw rod, an annular rack and a transmission gear that are placed in the shell and between the resistor body and the collector ring. The two ends of the two parallel connecting guide rods are respectively connected to the end plates, the connecting guide rod and the drive shaft are perpendicular to each other and the middle sections of the two connecting guide rods are connected to the middle section of the drive shaft, the screw rod and the connecting guide rod are parallel to each other and are located between the two connecting guide rods, the positions close to the two ends on the screw rod are respectively connected to the two end plates through bearings, the middle section of the screw rod passes through the corresponding through holes on the drive shaft and do not contact each other, and the annular transmission The moving gear is sleeved on the outside of one end of the lead screw through its own central through hole and is meshed with the circular annular rack installed on the inner wall of the shell. The center line of the transmission gear and the center line of the annular rack are perpendicular to each other and parallel to the center line of the lead screw. The brush assembly includes an insulating brush holder, a conductive brush and a nut. The brush is installed on the brush holder and is in contact with the working belt on the resistor and the conductive belt on the collector ring at the same time. The nut is fixedly installed in the central through hole of the brush holder and sleeved on the outside of the lead screw and threadedly connected. Two guide through holes are provided on the brush holder and the two connecting guide rods pass through the two guide through holes respectively. The working belt on the resistor is a multi-turn spiral working belt located in the same plane.

2. The multi-turn angular displacement potentiometer based on a conductive plastic resistor according to claim 1, characterized in that: The elliptical brush formed by multiple annular closed brush wires arranged side by side is installed on the outer wall of the elliptical or elliptical brush holder, the two ends of the short axis of the brush are respectively connected to the two ends of the short axis of the brush holder, and gaps are left between the two ends of the long axis of the brush and the two ends of the long axis of the brush holder, and the two guide through holes are respectively arranged on the brush holder near the two ends of the long axis, and the two ends of the long axis of the brush are bent to form brush contact parts, and the two brush contact parts are respectively in contact with the working belt on the resistor and the conductive belt on the collector ring.

3. The multi-turn angular displacement potentiometer based on a conductive plastic resistor according to claim 2, characterized in that: The brush holder is a plastic holder, the nut is integrally molded with the brush holder, the two ends of the short shaft of the brush are respectively placed outside the two ends of the short shaft of the brush holder, and the two metal plates are respectively located outside the two ends of the short shaft of the brush and are respectively connected to the outer walls of the two ends of the short shaft of the brush holder through connecting screws.

4. The multi-turn angular displacement potentiometer based on a conductive plastic resistor according to claim 3, characterized in that: A through hole is provided at a position on the metal plate corresponding to the brush, and solder is provided in the through hole and in the surrounding area to achieve a fixed connection between the brush and the corresponding metal plate, and the two connecting screws are respectively located on both sides of the solder.

5. The multi-turn angular displacement potentiometer based on a conductive plastic resistor according to claim 3, characterized in that: The nut is provided with outwardly protruding nut bosses on opposite sides of one direction, and mounting holes are provided on the nut bosses. The nut is provided with outwardly protruding positioning bumps on opposite sides of the other direction, and the positioning bumps are embedded in the brush holder.

6. The multi-turn angular displacement potentiometer based on a conductive plastic resistor according to claim 5, characterized in that: The multi-turn angular displacement potentiometer based on a conductive plastic resistor also includes an anti-backlash seat, a screw hole is provided in the middle of the anti-backlash seat, and the lead screw passes through the screw hole and is threadedly connected, two guide through holes are provided on the anti-backlash seat, and the two connecting guide rods pass through the two guide through holes respectively, a mounting groove is provided on the side surface of the brush holder close to the anti-backlash seat at a position corresponding to the nut boss, and the two nut bosses are respectively placed in the corresponding mounting grooves, one end of two mutually parallel anti-backlash springs are respectively connected to the mounting holes on the two nut bosses and placed in the corresponding mounting grooves, and the other ends of the two anti-backlash springs are respectively connected to the anti-backlash seat.

7. The multi-turn angular displacement potentiometer based on a conductive plastic resistor according to claim 2, characterized in that: The bending angle of the two brush contact parts of the brush is 60°-120°.

8. The multi-turn angular displacement potentiometer based on a conductive plastic resistor according to any one of claims 1 to 7, characterized in that: The outer diameter of the middle section of the driving shaft increases to form a large diameter section, the middle sections of the two connecting guide rods respectively pass through the corresponding through holes on the large diameter section and are connected by pins, and the middle sections of the screw rods pass through the corresponding through holes on the large diameter section without contacting each other.

9. The multi-turn angular displacement potentiometer based on a conductive plastic resistor according to any one of claims 1 to 7, characterized in that: The shell includes a shell seat, a shell tube and a shell cover, the two ends of the shell tube are respectively connected to the shell seat and the shell cover by screws, the resistor is installed on the inner wall of the shell seat, the annular rack is installed on the inner wall of the shell tube and close to the shell cover, the collector ring is installed on the inner wall of the shell cover, the drive shaft passes through the corresponding through hole on the shell cover and one end thereof is connected to the shell seat, the two ends of the working belt on the resistor are respectively connected to the inner end of the power lead, the conductive belt on the collector ring is connected to the inner end of the signal lead, the outer end of the power lead and the outer end of the signal lead respectively pass through the corresponding through holes on the shell tube and are placed outside the shell.

10. The multi-turn angular displacement potentiometer based on a conductive plastic resistor according to any one of claims 1 to 7, characterized in that: The transmission gear comprises a first transmission gear and a second transmission gear arranged in parallel, a torsion spring is installed between the first transmission gear and the second transmission gear and they together form an anti-backlash gear.

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