CN220341069U - Limit switch structure and rotary limit switch based on hall sensor and magnet - Google Patents

Abstract

The utility model provides a limit switch structure based on a Hall sensor and a magnet and a rotary limit switch. The limit switch structure based on the Hall sensor and the magnet comprises a transmission shaft, a rotating wheel set and a sensor bracket; the sensor bracket is positioned at the bottom of the rotating wheel group; a Hall sensor is arranged on the sensor bracket; the rotating wheel set is arranged on the transmission shaft; the rotating wheel group comprises a plurality of rotating wheels which are sequentially arranged; the rotating wheel is provided with a magnet; the transmission shaft can drive the magnet to rotate through the rotating wheel; the magnet rotates closer to or farther from the hall sensor. The limit switch structure based on the Hall sensor and the magnet overcomes the defect of the conventional limit of the rotary cam by changing the form and the triggering mode of the existing cam piece. The triggering mode of the limit switch structure is realized by detecting a magnet through a Hall sensor. Therefore, the defects of low positioning precision and large hysteresis area existing in the prior rotary cam limit are overcome.

Description

Limit switch structure and rotary limit switch based on hall sensor and magnet

Technical Field

The utility model relates to the field of cranes, in particular to a limit switch structure based on a Hall sensor and a magnet and a rotary limit switch.

Background

As a large-load hoisting machine, the crane is widely applied to heavy industrial enterprises, and the rotary cam limit is a necessary safety detection limit of the crane, so that the crane has a critical effect on the safety of the crane. In other mechanical devices, the rotary cam limit has also been widely used. The rotary cam limit mainly uses the detection safety position as a main function, and plays a vital role in the safe operation of mechanical equipment such as a crane.

The rotary cam limiting commonly used in the current market takes a cam plate as a main body, and the rotary cam plate touches the micro switch to enable the micro switch to act, so that a safety interlocking signal is provided for application equipment, and the safe operation of the application equipment is ensured. However, due to the adoption of the cam limiting mode, the action of the micro switch is in a hysteresis section, namely, the position from breaking to conducting and the position from conducting to breaking are not in one physical position, so that the deviation of the physical position of the safety chain is caused, and the precision is reduced.

Disclosure of Invention

Aiming at the defects in the prior art, the utility model aims to provide a limit switch structure based on a Hall sensor and a magnet and a rotary limit switch.

The limit switch structure based on the Hall sensor and the magnet comprises a transmission shaft, a rotating wheel set and a sensor bracket;

the sensor bracket is positioned at the bottom of the rotating wheel group;

a Hall sensor is arranged on the sensor bracket; the rotating wheel set is arranged on the transmission shaft;

the rotating wheel group comprises a plurality of rotating wheels which are sequentially arranged; the rotating wheel is provided with a magnet;

the transmission shaft can drive the magnet to rotate through the rotating wheel; the magnet rotates closer to or farther from the hall sensor.

Preferably, the number of the rotating wheels is 12,

the limit switch structure based on the Hall sensor and the magnet further comprises a first circuit board and a second circuit board;

the first circuit board and the second circuit board are respectively and electrically connected with 6 Hall sensors.

Preferably, the circuit further comprises an operating circuit;

the working circuit comprises 6 groups of unit circuits, wherein each group of unit circuits comprises an output connector, a follow current diode of a relay, a power connector, a sensor connector, an output relay, a driving transistor of the output relay, a pull-up resistor of a Hall sensor and a base resistor of the driving transistor;

the network tag in the sensor connector is connected with the output end of the Hall sensor;

the 1 pin of the output relay contact is a common end, the 3 pin of the output connector is connected, the 3 pin of the output relay is a normal open end, the 1 pin of the output connector is connected, the 2 pin of the output relay is a normal closed end, the 2 pin of the output connector is connected, the 5 pin of the coil of the output relay is connected with the collector electrode of the driving transistor, and the 4 pin of the coil of the output relay is grounded;

the positive electrode of the freewheel diode is grounded, and the negative electrode of the freewheel diode is connected with the 5 pin of the output relay coil;

an output transistor PNP type transistor;

the emitter of the output transistor is connected with VCC, the collector is connected with the 5 pin of the coil of the output relay, and the base is connected with the 2 pin of the base resistor;

the 1 pin of the pull-up resistor is connected with the output end of the Hall sensor, and the 2 pin is connected with the power VCC;

the 1 pin of the base resistor is connected with the output end of the Hall sensor and the 1 pin of the pull-up resistor, and the 2 pin of the base resistor is connected with the base of the driving transistor.

Preferably, the magnet is an arc-shaped strip magnet, and the arc center of the magnet is concentric with the rotating wheel; the central angle of the magnet is 5 degrees, 15 degrees, 30 degrees, 90 degrees or 180 degrees.

Preferably, the transmission device further comprises an input shaft, wherein the input shaft is connected with the transmission shaft through a gear set.

Preferably, the gear set includes a first speed change gear, a second speed change gear, a third speed change gear, a fourth speed change gear, and a fifth speed change gear;

the two ends of the input shaft are both provided with input shaft keys, the input shaft keys at the rear end are matched with a first speed change gear, the first speed change gear is meshed with a second speed change gear, the second speed change gear is a double-layer gear, the top layer is a pinion, the bottom layer is a bull gear, and the bull gear is meshed with the first speed change gear;

the second speed change gear is meshed with the third speed change gear;

the third speed change gear is a double-layer gear, the top layer is a large gear, the bottom layer is a small gear, and the large gear is meshed with the small gear of the second speed change gear;

the third speed change gear is meshed with a fourth speed change gear, the fourth speed change gear is a double-layer gear, the top layer is a pinion, the bottom layer is a large gear, and the large gear is meshed with the pinion of the third speed change gear;

the fourth speed change gear is meshed with the fifth speed change gear; the fifth speed change gear is a single-layer gear and is arranged on the transmission shaft.

Preferably, the device also comprises a transmission shaft locking ring, a fastening ring, an intermediate rotating wheel locking ring and a tail rotating wheel locking ring;

the head part of the transmission shaft is provided with a transmission shaft locking ring; an intermediate rotary wheel locking ring is arranged between the front end of the head rotary wheel and each rotary wheel, and the tail end of the tail rotary wheel is provided with a tail rotary wheel locking ring;

the transmission shaft locking ring is tightly clung to the middle rotary wheel locking ring of the head part, the tail part of the transmission shaft is movably provided with a fastening ring, and the fastening ring can move along the length direction of the transmission shaft.

Preferably, anti-slip protrusions are processed on two sides of the locking ring of the middle rotating wheel, and anti-slip protrusions are processed on one side of the locking ring of the tail rotating wheel;

the centre bore circumference of swiveling wheel has arranged the anti-skidding groove, the non-skidding arch can be mutually matched with the anti-skidding groove.

Preferably, key grooves are formed in the middle rotary wheel locking ring and the tail rotary wheel locking ring;

a plurality of locking keys are uniformly arranged on the transmission shaft and can be matched with key grooves on the middle rotary wheel locking ring and key grooves on the tail rotary wheel locking ring.

According to the rotary limit switch provided by the utility model, the limit switch structure based on the Hall sensor and the magnet is adopted.

Compared with the prior art, the utility model has the following beneficial effects:

the limit switch structure based on the Hall sensor and the magnet overcomes the defect of the conventional limit of the rotary cam by changing the form and the triggering mode of the existing cam piece. A limit switch structure based on a Hall sensor and a magnet adopts a rotating wheel to replace a traditional cam, a magnet is embedded at the inner edge of the rotating wheel, and the magnet is driven to rotate by the rotation of the rotating wheel. The triggering mode of the limit switch structure is realized by detecting the magnet through a Hall sensor, rather than the traditional cam scheme. Therefore, the defects of low positioning precision and large hysteresis area existing in the prior rotary cam limit are overcome.

Drawings

Other features, objects and advantages of the present utility model will become more apparent upon reading of the detailed description of non-limiting embodiments, given with reference to the accompanying drawings in which:

FIG. 1 is an overall block diagram of a rotary limit switch, in which a limit switch structure based on a Hall sensor and a magnet is embodied;

FIG. 2 is a schematic diagram of an instrument panel arrangement of the adjustment bin;

FIG. 3 is a diagram of a 6 th instrument panel arrangement;

FIG. 4 is a schematic diagram of a rotating wheel structure;

FIG. 5 is a schematic side view of a rotating wheelset configuration;

FIG. 6 is a schematic bottom view of a rotating wheelset configuration;

FIG. 7 is a schematic view of two views of an intermediate rotary wheel locking ring;

FIG. 8 is a schematic view of a tail rotor locking ring in three views;

FIG. 9 is a schematic diagram of two views of a sensor mount;

FIG. 10 is a partial structural side view of a rotary limit switch;

FIG. 11 is a schematic view of a partial structure of a rotary limit switch;

FIG. 12 is a schematic view of a scale indicator from two sides;

FIG. 13 is a schematic diagram of a block diagram of an input shaft;

FIG. 14 is a schematic view of a structure of a drive shaft;

fig. 15 is a circuit diagram of a limit switch structure.

The figure shows:

Detailed Description

The present utility model will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the present utility model, but are not intended to limit the utility model in any way. It should be noted that variations and modifications could be made by those skilled in the art without departing from the inventive concept. These are all within the scope of the present utility model.

The utility model provides a limit switch structure based on a Hall sensor and a magnet, which comprises a transmission shaft 1, a rotating wheel set 2 and a sensor bracket 19; the sensor bracket 19 is positioned at the bottom of the rotating wheel set 2; the sensor bracket 19 is provided with a Hall sensor 191; the rotating wheel set 2 is arranged on the transmission shaft 1; the rotating wheel set 2 comprises a plurality of rotating wheels 3 which are sequentially arranged; the rotating wheel 3 is provided with a magnet 31; the transmission shaft 1 can drive the magnet 31 to rotate through the rotating wheel 3, and the transmission shaft 1 can drive the magnet 31 to rotate through the rotating wheel 3; the magnet 31 rotates toward or away from the hall sensor 191.

When magnet 31 rotates to the hall sensor position, hall sensor 191 is triggered, i.e., limit switch structure is triggered; when magnet 31 is disengaged from the hall sensor, hall sensor 191 returns to the unactuated state, i.e., the limit switch structure returns to the unactuated state.

The number of the rotating wheels 3 is 12, and the limit switch structure based on the Hall sensor and the magnet further comprises a first circuit board 13 and a second circuit board 14; the first circuit board 13 and the second circuit board 14 are electrically connected to 6 hall sensors 191, respectively.

The sensor bracket is also provided with a PCB circuit 192, and the PCB circuit 192 leads out pins of the Hall sensor and is then connected to the first circuit board 13 and the second circuit board 14, so that the corresponding relay is driven to complete the triggering action of the rotating wheel 3.

In a preferred embodiment, the number of the rotating wheels 3 is 12, and the number of the hall sensors 191 is also 12.

The rotary wheel 3 is provided with 36 rotary wheel scales which are distributed at the edge position of the rotary wheel 3 at equal intervals, each scale represents 10 degrees, and scale reading numbers are processed at every 30 degrees from 0 degrees. The whole rotating wheel 3 is a gear with the modulus of 0.5, the edge of the rotating wheel is 120 teeth, and the edge of the central hole is provided with a rotating wheel anti-skid groove 324.

The magnet 31 is an arc-shaped strip magnet, and is formed by processing a neodymium magnet, and the magnetic poles of the neodymium magnet are positioned on two sides of the arc-shaped strip. The arc circle center is concentric with the rotating wheel 3; the central angle of magnet 31 is 5 degrees, 15 degrees, 30 degrees, 90 degrees or 180 degrees, including but not limited to these angles, and generally, the central angle of magnet 31 may be any angle to accommodate different process requirements. The smaller the central angle of magnet 31, the shorter the arc length of magnet 31, and the smaller the trigger zone of rotary wheel 3, whereas the larger the central angle of magnet 31, the longer the arc length of magnet 31, and the larger the trigger zone of rotary wheel 3. The requirements of the trigger intervals of the rotating wheel 3 are different according to different process requirements, so that the central angles of the magnets 31 are also different, and different magnets 31 can be customized for different process requirements.

The limit switch structure based on the Hall sensor and the magnet further comprises an input shaft 15, and the input shaft 15 is connected with the transmission shaft 1 through the gear set 12.

The reason why the limit switch structure based on the hall sensor and the magnet is designed with the gear set 12 is that since the limit switch structure is usually mounted on the wire rope reel, the input shaft and the wire rope reel rotate coaxially, and the wire rope reel rotates normally for a plurality of turns in the full stroke, the rotating wheel 3 does not rotate for a plurality of turns, otherwise, the triggering signal will trigger for a plurality of times in the full stroke, so that the identification cannot be performed. A gear set 12 is therefore preferably added between the input shaft of the limit switch arrangement and the rotating wheel 3 for changing the speed ratio between the input shaft and the rotating wheel set 2.

The gear set 12 includes a first ratio gear 121, a second ratio gear 122, a third ratio gear 123, a fourth ratio gear 124, and a fifth ratio gear 125; input shaft key 151 has all been processed at input shaft 15 both ends, and the input shaft key 151 of front end is used for wire rope reel axle and based on the cooperation of hall sensor and magnet limit switch structure, and the input shaft key 151 of rear end cooperates with first speed change gear 121, ensures first speed change gear 121 and input shaft synchronous revolution. The first speed change gear 121 is meshed with the second speed change gear 122, the second speed change gear 122 is a double-layer gear, the top layer is a small gear, the bottom layer is a large gear, and the large gear is meshed with the first speed change gear 121; the second speed gear 122 is meshed with the third speed gear 123; the third speed change gear 123 is a double-layer gear, the top layer is a large gear, and the bottom layer is a small gear, wherein the large gear is meshed with the small gear of the second speed change gear 122; the third speed change gear 123 is meshed with the fourth speed change gear 124, the fourth speed change gear 124 is a double-layer gear, the top layer is a pinion, the bottom layer is a large gear, and the large gear is meshed with the pinion of the third speed change gear 123; the fourth speed gear 124 meshes with a fifth speed gear 125; the fifth speed-changing gear 125 is a single-layer gear, the fifth speed-changing gear 125 is installed on the transmission shaft 1, the transmission shaft is provided with a key, the fifth speed-changing gear 125 is provided with a key groove, and the fifth speed-changing gear 125 and the transmission shaft can synchronously rotate by matching with the key of the transmission shaft. Specifically, the first speed change gear 121 has the number of teeth 25; the number of large gear teeth 50 and the number of small gear teeth 30 of the second speed change gear 122; the third change gear 123 has a large gear number 30 and a small gear number 10; the fourth change gear 124 has a large gear number 40 and a small gear number 10; the number of teeth 50 of the fifth ratio gear 125. All ratio gears have a modulus of 0.5 and a pressure angle of 20 degrees. The speed ratio between the input shaft and the transmission shaft of the utility model is 40:1. in addition, the speed ratio between the input shaft and the transmission shaft of the limit switch structure based on the hall sensor and the magnet can be adjusted by changing the speed ratio between the large gear of the third speed change gear and the small gear of the fourth speed change gear 124 to be suitable for other process situations.

The limit switch structure based on the Hall sensor and the magnet further comprises a transmission shaft locking ring 16, an intermediate rotating wheel locking ring 32 and a tail rotating wheel locking ring 33; the head part of the transmission shaft 1 is provided with a transmission shaft locking ring 16; an intermediate rotary wheel locking ring 32 is arranged between the front end of the head rotary wheel 3 and each rotary wheel 3, and 12 rotary wheels 3, the intermediate rotary wheel locking ring 32 and the tail rotary wheel locking ring 33 are concentrically arranged on the transmission shaft 1. The tail end of the tail rotary wheel 3 is provided with a tail rotary wheel locking ring 33; the transmission shaft locking ring 16 is tightly clung to the middle rotary wheel locking ring 32 at the head part, the tail part of the transmission shaft 1 is movably provided with a fastening ring 17, and the fastening ring 17 can move along the length direction of the transmission shaft 1. Specifically, the tail of the transmission shaft is provided with external threads, the fastening ring 17 is provided with internal threads matched with the threads of the tail of the transmission shaft, and the fastening ring 17 can be screwed on the transmission shaft. The fastening ring 17 can be tightly attached to the tail rotary wheel locking ring 33 when the fastening ring 17 is screwed on the transmission shaft, the middle rotary wheel locking ring 32, the rotary wheel set 2 and the tail rotary wheel locking ring 33 are fastened together when the fastening ring 17 is screwed, and specifically, when the fastening ring 17 is screwed on, the fastening ring 17 compresses the tail rotary wheel locking ring 33, so that the middle rotary wheel locking ring 32 and the rotary wheel set 2 of the tail rotary wheel locking ring 33 are compressed together. The whole body formed by the middle rotary wheel locking ring 32 of the tail rotary wheel locking ring 33, the middle rotary wheel locking ring 32 of the rotary wheel set 2, the rotary wheel set 2 and the tail rotary wheel locking ring 33 is also fastened together with the transmission shaft 1, so that the rotary wheel set 2 and the transmission shaft 1 can move together.

Specifically, the two sides of the locking ring 32 of the middle rotating wheel are provided with the anti-slip protrusions 321, one side of the locking ring 33 of the tail rotating wheel is provided with the anti-slip protrusions 321, one side with the anti-slip protrusions is clung to the rotating wheel 3 during installation, more specifically, the central hole of the rotating wheel 3 is circumferentially provided with the anti-slip grooves 324, and the anti-slip protrusions 321 can be matched with the anti-slip grooves 324.

The middle rotary wheel locking ring 32 and the tail rotary wheel locking ring 33 are provided with key grooves 322; a plurality of locking keys 323 are uniformly arranged on the drive shaft 1, and preferably, the number of the locking keys 323 is 13. The locking key 323 is capable of cooperating with a keyway on the intermediate rotary wheel locking ring 32 and a keyway on the tail rotary wheel locking ring 33. It is ensured that the intermediate rotary wheel locking ring 32 and the tail rotary wheel locking ring 33 can only slide axially along the drive shaft, but cannot rotate along the drive shaft. The swivel wheel 3 is mounted in the middle of the two locking keys of the drive shaft, so that when the fastening ring 17 is released, the swivel wheel 3 can rotate freely along the drive shaft without affecting the other swivel wheels 3.

When the anti-slip boss 321 is matched with the anti-slip groove 324 to strengthen the friction force between the rotating wheel 3 and the middle rotating wheel locking ring 32 and the tail rotating wheel locking ring 33 when the fastening ring 17 is screwed, and meanwhile, the locking key of the transmission shaft is matched with the key grooves of the middle rotating wheel locking ring 32 and the tail rotating wheel locking ring 33 so that the middle rotating wheel locking ring 32 and the tail rotating wheel locking ring 33 can not rotate along the transmission shaft, thereby ensuring more reliable synchronization of the rotating wheel 3 and the transmission shaft.

The limit switch structure based on the Hall sensor and the magnet further comprises a working circuit; the working circuit comprises 6 groups of unit circuits, wherein each group of unit circuits comprises an output connector, a follow current diode of a relay, a power connector, a sensor connector, an output relay, a driving transistor of the output relay, a pull-up resistor of a Hall sensor and a base resistor of the driving transistor; the network tag in the sensor connector is connected with the output end of the Hall sensor; the 1 pin of the output relay contact is a common end, the 3 pin of the output connector is connected, the 3 pin of the output relay is a normal open end, the 1 pin of the output connector is connected, the 2 pin of the output relay is a normal closed end, the 2 pin of the output connector is connected, the 5 pin of the coil of the output relay is connected with the collector electrode of the driving transistor, and the 4 pin of the coil of the output relay is grounded; the positive electrode of the freewheel diode is grounded, and the negative electrode of the freewheel diode is connected with the 5 pin of the output relay coil; an output transistor PNP type transistor; the emitter of the output transistor is connected with VCC, the collector is connected with the 5 pin of the coil of the output relay, and the base is connected with the 2 pin of the base resistor; the 1 pin of the pull-up resistor is connected with the output end of the Hall sensor, and the 2 pin is connected with the power VCC; the 1 pin of the base resistor is connected with the output end of the Hall sensor and the 1 pin of the pull-up resistor, and the 2 pin of the base resistor is connected with the base of the driving transistor.

Specifically, fig. 15 is a circuit diagram of the limit switch structure based on the hall sensor and the magnet. The circuit is formed by combining 6 groups of unit circuits, wherein elements J1 to J6 are output connectors, elements D1 to D6 are flywheel diodes of relays, element J11 is a power connector, element J12 is a sensor connector, elements K1 to K6 are output relays, elements Q1 to Q6 are driving transistors of the output relays, elements R1 to R6 are pull-up resistors of the Hall sensors, elements R11 to R16 are base resistors of the driving transistors, and network tags T1 to T6 in J12 are connected with output ends of the Hall sensors and are input signal nodes of a circuit diagram.

The output relay is a final node state output element based on the limit switch structure of the Hall sensor and the magnet, the 1 pin of the contact is a common end, the 3 pin of the contact is connected with the 3 pin of the output connector, the 3 pin is a normal open end, the 1 pin of the output connector is connected, the 2 pin is a normal closed end, the 2 pin of the output connector is connected, the 5 pin of the coil is connected with the collector electrode of the driving transistor, and the 4 pin of the coil is grounded; the positive electrode of the freewheel diode is grounded, and the negative electrode of the freewheel diode is connected with the 5 pin of the output relay coil; the output transistor is used for driving the action state of the relay, the driving transistor is a PNP type low-power transistor, a common 8550 transistor can be selected, the emitter of the output transistor is connected with VCC, the collector of the output transistor is connected with the 5 pin of the coil of the output relay, and the base of the output transistor is connected with the 2 pin of the base resistor; the 1 pin of the pull-up resistor is connected with the output end of the Hall sensor, and the 2 pin is connected with the power VCC; the base resistor is used for limiting the current of the output of the Hall sensor, the 1 pin of the base resistor is connected with the output end of the Hall sensor and the 1 pin of the pull-up resistor, and the 2 pin of the base resistor is connected with the base of the driving transistor.

The Hall sensor based on the selection of the limit switch structure of the Hall sensor and the magnet is a switch type, and the type of the Hall sensor is normally open type. When the trigger is not triggered, the output end of the Hall sensor is at a high level, the level is close to VCC, and when the trigger is triggered, the output end of the Hall sensor is at a low level, and the level is close to 0V. When the hall sensor is not triggered, the driving transistor will be turned off because its output is close to VCC, the output relay coil cannot be powered, and therefore the contacts of the output relay remain intact. When the Hall sensor is triggered, the output of the Hall sensor is close to 0V, so that the driving transistor is conducted, the output relay coil is electrified, and therefore the contact state of the output relay is turned over, and node state information can be output.

The utility model also provides a rotary limit switch, which is shown in figures 1-15, and further comprises an adjusting structure and an instrument panel structure by adopting the limit switch structure based on the Hall sensor and the magnet. The instrument panel structure, the adjusting structure and the rotating wheel set 2 are sequentially connected in a transmission way;

the instrument panel structure comprises a plurality of instrument panel groups 4, wherein each instrument panel group comprises a plurality of instrument panels 5 and a rotary wheel indication mark 6; the number of the instrument panels 5 is 2, and the instrument panels are respectively a subdivision adjustment dial 51 and a rough subdivision adjustment dial 52; the single-way instrument panel group corresponds to one adjusting structure one by one.

The adjusting structure comprises a subdivision adjusting gear 7, a rough subdivision adjusting gear 8, a subdivision adjusting shaft 9 and a rough subdivision adjusting shaft 10; the subdivision adjusting gear 7 is mounted on the subdivision adjusting shaft 9, and the subdivision adjusting gear 7 rotates in synchronization with the subdivision adjusting shaft 9; the rough-separation adjusting gear 8 is mounted on the rough-separation adjusting shaft 10, and the rough-separation adjusting gear 8 rotates in synchronization with the rough-separation adjusting shaft 10; the subdivision adjusting gear 7, the rough subdivision adjusting gear 8 and the rotating wheel 3 are meshed in sequence;

the subdivision adjustment dial 51 and the rough subdivision adjustment dial 52 are respectively mounted at the end of the subdivision adjustment shaft 9 and the end of the rough subdivision adjustment shaft 10; a subdivision adjustment pointer 511 is arranged in the subdivision adjustment dial 51, and the subdivision adjustment pointer 511 can drive the subdivision adjustment shaft 9 to rotate; the subdivision adjusting gear 7 can thus be driven to rotate, so that the rotary wheel 3 is rotated.

A rough adjustment pointer 521 is arranged in the rough adjustment dial 52; the rough adjustment pointer 521 can drive the rough adjustment shaft 10 to rotate; the rough adjusting gear 8 can thus be driven to rotate, thereby realizing the rotation of the rotating wheel 3.

The rotary wheel 3 is provided with wheel disc scales. The scale indicator bracket 18 is installed at the top of the rotating wheel group 2, a plurality of scale indicators 181 are installed on the scale indicator bracket 18, each scale indicator corresponds to one rotating wheel 3 one by one, the scale indicators are triangular metal sheets, and the scale indicators are matched with scales on a rotating wheel 3 disc to indicate the rotating angle of the rotating wheel 3.

The subdivision adjustment dial 51 is a 1-degree subdivision adjustment dial; the rough adjustment dial 52 is a 30-degree rough adjustment dial; the subdivision adjusting gear 7 is a 1-degree subdivision adjusting gear; the rough-separation adjusting gear 8 is a 30-degree rough-separation adjusting gear; the subdivision adjustment axis 9 is a 1-degree subdivision adjustment axis, and the coarse subdivision adjustment axis 10 is a 30-degree coarse subdivision adjustment axis 10.

The subdivision adjusting gear 7 is a single-layer gear, the number of teeth is 10, and the modulus is 0.5; the rough-separation adjusting gear 8 is a large-small double-layer gear, the number of teeth of the large gear is 30 teeth, the modulus is 0.5, the number of teeth of the small gear is 10 teeth, and the modulus is 0.5. The subdivision adjusting gear 7 is meshed with a large gear of the rough-division adjusting gear 8, and a small gear of the rough-division adjusting gear 8 is meshed with the rotating wheel 3.

The fine adjustment pointer 511 and the rough adjustment pointer 521 are provided with adjustment holes in the middle, and an operator can rotate the fine adjustment pointer 511 and the rough adjustment pointer 521 through the adjustment holes. In a preferred embodiment, the adjusting hole is a square hole, and an operator can rotate the 1-degree fine-division adjusting pointer or the 30-degree coarse-division adjusting pointer by matching the square hole through a 1-shaped screwdriver, so that the adjustment of the rotating wheel 3 is realized. Thereby realizing the adjustment of the interlocking position of the rotary limit switch. The accurate angle adjustment can be realized by matching with the scales of the instrument panel. On the contrary, when the rotary limit switch works, the rotary wheel 3 can drive the rotation of the 1-degree subdivision adjusting pointer and the 30-degree coarse-division adjusting pointer along with the rotation of the transmission shaft, and the corresponding rotary wheel 3 rotation angle can be indicated by matching with the indication mark of the rotary wheel set 2, so that the record and the reference are facilitated.

The rotary limit switch further comprises an instrument bin 11, and the instrument panel structure is located in the instrument bin 11. In a preferred embodiment, the rotating wheels 3 are in a gear structure, the number of the rotating wheels 3 is 12, the 12 rotating wheels 3 are all sleeved on the transmission shaft 1, the instrument panel sets 4 are 12 paths, the 12 paths of instrument panel sets 4 are vertically and symmetrically arranged on two sides of the center of the instrument bin on the instrument panel, 6 instrument panel sets on each side are circumferentially arranged on the center of the transmission shaft, the initial angle of the center line of the upper instrument panel set 4 of each instrument panel set 4 on each side is 50 degrees, the interval angle of the center lines of the adjacent instrument panel sets 4 on the same side is 20 degrees, and at the moment, the number of the adjusting structures is also 12.

Specifically, 10 big scales are altogether processed on the 1-degree subdivision adjustment dial plate, the big scales are distributed at the edge position of the 1-degree subdivision adjustment dial plate at equal intervals, each big scale represents 1 degree, scale reading numbers are processed on even number big scale positions, 5 small scales are processed between every two big scales, the big scales are distributed at equal intervals, and each small scale represents 0.2 degree. The 1-degree subdivision adjustment dial further includes a 1-degree subdivision adjustment pointer for indicating the adjustment position. The 30-degree rough-separation adjustment dial plate is provided with 30 scales, the scales are distributed at the edge position of the 30-degree rough-separation adjustment dial plate at equal intervals, each scale represents 1 degree, scale reading numbers are processed at the scale positions of 0 degree, 10 degrees and 20 degrees, and the 30-degree rough-separation adjustment dial plate further comprises 30-degree rough-separation adjustment pointers. The rotary wheel set 2 indication mark is processed with a digital mark of the rotary wheel set 2 group. More specifically, the speed ratio of the 30-degree rough-separation adjusting gear to the rotating wheel 3 is 12: the ratio of the 1,1 degree subdivision regulating gear to the 30 degree coarse subdivision regulating gear is 3:1. thus, the 30-degree rough adjusting gear rotates 1 degree, the rotating wheel 3 rotates 1/30 degree, and the 1-degree fine adjusting gear rotates 1 degree, and the rotating wheel 3 rotates 1/10 degree. The minimum scale of the 1-degree subdivision adjustment dial plate is 0.2 degrees, so that the accurate adjustment precision of the 1-degree subdivision adjustment gear can reach 0.2 degrees, and the estimated reading can reach 0.1 degrees.

When the fastening ring 17 is loosened, the rotating wheel 3 and the adjacent middle rotating wheel locking ring 32 are loosened, at the moment, the 1-degree subdivision adjusting gear or the 30-degree rough subdivision adjusting gear is adjusted, the corresponding rotating wheel 3 can be rotated, at the moment, the adjacent middle rotating wheel locking ring 32 is loosened with the rotating wheel 3 and cannot rotate due to the matching of the locking keys, so that the rotation of the adjusted rotating wheel 3 can be ensured to rotate only between the two adjacent locking rings, and other rotating wheels 3 can not be driven to rotate, and the adjustment flexibility and reliability are ensured.

The rotary limit switch further comprises a rotary wheel house 22 cover plate, an instrument house cover plate and a shell 20. The housing 20 includes a shift house 21, a rotary wheel house 22, a first electrical house 23, a second electrical house 24, a rotary wheel house cover mounting post 25, an adjustment house cover mounting post 26, and a mounting bracket 27. The rotary wheel house cover plate mounting column 25 is provided with a rotary wheel house 22 cover plate mounting hole for mounting a rotary wheel house 22 top cover plate and a rotary wheel house 22 bottom cover plate. The cover plate of the rotary wheel bin 22 comprises a top cover plate of the rotary wheel bin 22, a bottom cover plate of the rotary wheel bin 22 and an adjusting bin cover plate, wherein the top cover plate of the rotary wheel bin 22, the bottom cover plate of the rotary wheel bin 22 and the instrument bin cover plate are all metal cover plates, and the rotary wheel bin 22 is simple in structure and is only a shell sealing component of the utility model, and has no substantial effect on the principle and the function of the utility model, so that the rotary wheel bin 22 is not shown in the drawings. The mounting bracket is machined with mounting holes 28 so that the rotary limit switch can be conveniently mounted on external application equipment.

The gear set 12 is installed in the speed changing bin 21, the rotating wheel set 2 is located in the rotating wheel bin 22, and the first circuit board 13 and the second circuit board 14 are installed in the first electric bin 23 and the second electric bin 24 respectively.

The bottom cover plate of the rotary wheel house 22 is fitted with cable connectors for connecting the electrical signals and power of the first and second circuit boards 13, 14 to the outside of the housing for signal acquisition and power supply of the application device.

In addition, since the rotary wheel house 22 has a compact internal structure and a limited space, the fastening and releasing of the fastening ring 17 cannot be operated by an universal wrench. In order to facilitate the fastening and loosening of the fastening ring, the outer edge of the fastening ring is provided with a fastening hole, and the fastening ring can be fastened on the transmission shaft or loosened from the transmission shaft by inserting a universal cross screwdriver into the fastening hole to move back and forth. The adjacent surfaces of the fastening ring 17 and the tail rotating wheel locking ring 33 are smooth surfaces, so that the fastening and loosening rotation resistance of the fastening ring is small, and the fastening of the whole rotating wheel set 2 can be ensured to be easier and more reliable. When the fastening ring 17 is loosened, the rotating wheel 3 and the adjacent middle rotating wheel locking ring 32 are loosened, at the moment, the 1-degree subdivision adjusting gear or the 30-degree rough subdivision adjusting gear is adjusted, the corresponding rotating wheel 3 can be rotated, at the moment, the adjacent middle rotating wheel locking ring 32 is loosened with the rotating wheel 3 and cannot rotate due to the matching of the locking keys, so that the rotation of the adjusted rotating wheel 3 can be ensured to rotate only between the two adjacent locking rings, and other rotating wheels 3 can not be driven to rotate, and the adjustment flexibility and reliability are ensured.

The rotary limit switch is simpler in working principle, and is usually installed on a steel wire rope winding drum of application equipment, and an input shaft of the rotary limit switch is connected with the steel wire rope winding drum shaft, so that the input shaft of the rotary limit switch and the steel wire rope winding drum shaft synchronously rotate. The rotation of the rotary limit switch input shaft drives the rotary wheel set 2 to rotate after the gear set is decelerated, wherein the rotation of the rotary wheel 3 of the rotary wheel set 2 drives the magnet 31 to rotate, and when the magnet 31 rotates to the position of the Hall sensor, the Hall sensor is triggered. And when magnet 31 is disengaged from the hall sensor, the hall sensor will be restored to the non-triggered state. The magnets 31 of different rotary wheels 3 are different in length, so that the trigger strokes or the non-trigger strokes of the corresponding hall sensors are different.

The locking ring is loosened, the rotating wheel set 2 can be in an adjustable state, and then the corresponding rotating wheel 3 can be adjusted to rotate to a specific angle by adjusting the corresponding 1-degree subdivision adjusting pointer or 30-degree coarse adjustment pointer according to the indication mark of the rotating wheel set 2, so that the corresponding rotating wheel 3 can trigger the Hall sensor at a specific position of the whole stroke of the application equipment or be separated from the Hall sensor. After the adjustment is finished, the locking ring is fastened, so that the rotary wheel set 2 can synchronously rotate with the transmission shaft, and the rotary wheel set 2 can rotate with the input shaft according to the speed ratio of the gear set, so that the rotary wheel set 2 is in a working state. At this time, in the working process of the application equipment, the rotary wheel set 2 triggers the hall sensor at a plurality of specific positions in the course or is separated from the hall sensor, so that the output relay is attracted or separated at a plurality of specific positions in the course, and the safety position interlocking control of the application equipment is realized.

The current limit of the rotating cam in the market mainly uses the cam sheet to trigger the micro switch to realize the basic function of the cam limit, and the defects existing at present mainly are that the trigger point of the cam sheet is the inflection point of the cam, which is unlikely to be abrupt change, and the micro switch also has a hysteresis area, thereby leading to low adjustment precision of the cam limit and also leading to low positioning precision of the cam limit. If the problems can be solved, the accuracy and stability of the cam limit can be obviously improved, and the adjustment difficulty of the rotating cam limit can be effectively reduced.

The rotary limit switch overcomes the defect of the conventional rotary cam limit by changing the form, the triggering mode and the adjusting mode of the existing cam piece. The rotary limit switch adopts a large-diameter gear to replace the traditional cam, an arc-shaped magnet strip, namely a magnet, is embedded in the inner edge of the rotary wheel, and the magnet is driven to rotate by the rotation of the rotary wheel. The triggering mode of the rotary limit switch is realized by detecting the magnet through the Hall sensor. The hall sensor is a magnetically sensitive sensor, and when enough magnetic force lines pass through the hall element, the switching state of the hall element is turned over. Therefore, when the magnet reaches the position of the Hall sensor along with the rotation of the rotating wheel, the switch state of the Hall sensor is overturned, so that the triggering state of the rotary limit switch is realized. The edge of the trigger curve of the Hall sensor is steep, and the characteristic shows that the Hall sensor is sensitive in action, so that the detection precision can be effectively improved. In addition, although the Hall sensor trigger curve also has a hysteresis zone, the hysteresis zone is very small, if the magnet made of neodymium magnet is adopted, the magnetic line density of the magnet can be effectively improved, so that the change curve of the magnetic line density of the trigger edge is steeper, the hysteresis zone of the Hall sensor action can be reduced, and the displacement fed back to the input end by the hysteresis zone can be ignored. Therefore, the defects of low positioning precision and large hysteresis area of the early-stage rotating cam limit are overcome.

Another reason for the rotary limit switch to use a large gear (i.e., a rotating wheel) instead of a cam is that fine adjustment of the rotating wheel can be achieved through a gear change transmission. Another disadvantage of early cam limiting is the difficulty of adjustment, and the inability to achieve fine adjustment. The rotary limit switch provided by the utility model realizes variable speed transmission of the rotary wheel through the two-stage adjusting gear transmission, thereby realizing two-stage accurate adjustment of the rotary wheel, wherein the first-stage adjusting gear is 1/12 conversion ratio, the second-stage adjusting gear is 1/3 conversion ratio, namely, the first-stage adjusting gear rotates for one circle, the rotary wheel rotates for 30 degrees, the second-stage adjusting gear rotates for one circle, the rotary wheel rotates for 10 degrees, coarse adjustment can be realized through the first-stage adjusting gear, fine adjustment can be realized through the second-stage adjusting gear, the two-stage adjusting mode can obviously improve the adjusting efficiency and precision, the gear transmission is bidirectional, the accurate adjustment can be realized through matching with the adjusting indicator and the dial, the rotating position of the rotary wheel in operation can be observed, the data recording is convenient, and the adjusted rotary angle of the rotary wheel is convenient to be re-carved into the limit of the other rotary wheel. Therefore, the utility model overcomes the defect that the current cam limit is difficult to adjust.

The Hall sensor is an active element and needs a circuit to drive, the load capacity of the Hall sensor is small, the switching signal of the Hall sensor needs to be converted into the switching signal of the relay through the driving circuit, the conversion of an active node into a passive node is realized, and the load capacity is improved. The rotary limit switch realizes the conversion function through the circuit boards, and each circuit board can be simultaneously connected with six Hall sensors to realize six-path node conversion. When two circuit boards are adopted, the conversion of 12 paths of nodes can be realized. The rotary limit switch adopts a detection mode of a rotary wheel, a magnet and a Hall sensor, and the circuit only adopts a triode drive relay mode although the electronic elements participate, so that the circuit is simple and reliable, the main body part is mainly in mechanical transmission, the adaptability to severe environment is very high, the resistance to vibration is very high, and the rotary limit switch is matched with a two-stage adjustment mode, so that the defects of low positioning precision, hysteresis area and difficult adjustment of the limit of the rotary cam in the past can be overcome, and the defects of low service life and poor stability of the limit of the imported electronic cam in the severe working environment are overcome. Meanwhile, the device has the advantages of high stability and high adaptability to severe environments of the conventional rotary cam limit and the advantages of easiness in adjustment, high adjustment precision and high positioning precision of the inlet electronic cam limit.

In the description of the present application, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, merely to facilitate description of the present application and simplify the description, and do not indicate or imply that the devices or elements being referred to must have a specific orientation, be configured and operated in a specific orientation, and are not to be construed as limiting the present application.

The foregoing describes specific embodiments of the present utility model. It is to be understood that the utility model is not limited to the particular embodiments described above, and that various changes or modifications may be made by those skilled in the art within the scope of the appended claims without affecting the spirit of the utility model. The embodiments of the present application and features in the embodiments may be combined with each other arbitrarily without conflict.

Claims (10)

1. The limit switch structure based on the Hall sensor and the magnet is characterized by comprising a transmission shaft (1), a rotating wheel set (2) and a sensor bracket (19);

the sensor bracket (19) is positioned at the bottom of the rotating wheel set (2);

a Hall sensor (191) is arranged on the sensor bracket (19); the rotating wheel set (2) is arranged on the transmission shaft (1);

the rotating wheel group (2) comprises a plurality of rotating wheels (3) which are sequentially arranged; a magnet (31) is arranged on the rotating wheel (3);

the transmission shaft (1) can drive the magnet (31) to rotate through the rotating wheel (3); the magnet (31) rotates toward or away from the hall sensor (191).

2. The hall sensor and magnet based limit switch structure of claim 1, wherein,

the number of the rotating wheels (3) is 12,

the limit switch structure based on the Hall sensor and the magnet further comprises a first circuit board (13) and a second circuit board (14);

the first circuit board (13) and the second circuit board (14) are respectively and electrically connected with 6 Hall sensors (191).

3. The hall sensor and magnet based limit switch structure of claim 1, further comprising an operating circuit;

the working circuit comprises 6 groups of unit circuits, wherein each group of unit circuits comprises an output connector, a follow current diode of a relay, a power connector, a sensor connector, an output relay, a driving transistor of the output relay, a pull-up resistor of a Hall sensor and a base resistor of the driving transistor;

the network tag in the sensor connector is connected with the output end of the Hall sensor;

the 1 pin of the output relay contact is a common end, the 3 pin of the output connector is connected, the 3 pin of the output relay is a normal open end, the 1 pin of the output connector is connected, the 2 pin of the output relay is a normal closed end, the 2 pin of the output connector is connected, the 5 pin of the coil of the output relay is connected with the collector electrode of the driving transistor, and the 4 pin of the coil of the output relay is grounded;

the positive electrode of the freewheel diode is grounded, and the negative electrode of the freewheel diode is connected with the 5 pin of the output relay coil;

the output transistor is a PNP transistor;

the emitter of the output transistor is connected with VCC, the collector is connected with the 5 pin of the coil of the output relay, and the base is connected with the 2 pin of the base resistor;

the 1 pin of the pull-up resistor is connected with the output end of the Hall sensor, and the 2 pin is connected with the power VCC;

the 1 pin of the base resistor is connected with the output end of the Hall sensor and the 1 pin of the pull-up resistor, and the 2 pin of the base resistor is connected with the base of the driving transistor.

4. The limit switch structure based on the Hall sensor and the magnet according to claim 1, wherein the magnet (31) is an arc-shaped strip magnet, and the arc center of the arc-shaped strip magnet is concentric with the rotating wheel (3); the central angle of the magnet (31) is 5 degrees, 15 degrees, 30 degrees, 90 degrees or 180 degrees.

5. The limit switch structure based on a hall sensor and a magnet according to claim 1, further comprising an input shaft (15), the input shaft (15) being connected to the transmission shaft (1) through a gear set (12).

6. The hall sensor and magnet based limit switch structure of claim 5, wherein the gear set (12) comprises a first speed change gear (121), a second speed change gear (122), a third speed change gear (123), a fourth speed change gear (124), and a fifth speed change gear (125);

the two ends of the input shaft (15) are both provided with input shaft keys (151), the input shaft keys (151) at the rear end are matched with a first speed change gear (121), the first speed change gear (121) is meshed with a second speed change gear (122), the second speed change gear (122) is a double-layer gear, the top layer is a pinion, the bottom layer is a bull gear, and the bull gear is meshed with the first speed change gear (121);

the second speed change gear (122) is meshed with the third speed change gear (123);

the third speed change gear (123) is a double-layer gear, the top layer is a large gear, the bottom layer is a small gear, and the large gear is meshed with the small gear of the second speed change gear (122);

the third speed change gear (123) is meshed with a fourth speed change gear (124), the fourth speed change gear (124) is a double-layer gear, the top layer is a pinion, the bottom layer is a large gear, and the large gear is meshed with the pinion of the third speed change gear (123);

the fourth speed change gear (124) is meshed with the fifth speed change gear (125); the fifth speed change gear (125) is a single-layer gear, and the fifth speed change gear (125) is arranged on the transmission shaft (1).

7. The limit switch structure based on the hall sensor and the magnet according to claim 1, further comprising a transmission shaft locking ring (16), a fastening ring (17), an intermediate rotating wheel locking ring (32) and a tail rotating wheel locking ring (33);

a transmission shaft locking ring (16) is processed at the head part of the transmission shaft (1); an intermediate rotary wheel locking ring (32) is arranged between the front end of the head rotary wheel (3) and each rotary wheel (3), and the tail end of the tail rotary wheel (3) is provided with a tail rotary wheel locking ring (33);

the transmission shaft locking ring (16) is tightly clung to the middle rotary wheel locking ring (32) at the head part, the tail part of the transmission shaft (1) is movably provided with the fastening ring (17), and the fastening ring (17) can move along the length direction of the transmission shaft (1).

8. The limit switch structure based on the hall sensor and the magnet according to claim 1, wherein the anti-slip protrusions (321) are processed on two sides of the locking ring (32) of the middle rotary wheel, and the anti-slip protrusions (321) are processed on one side of the locking ring (33) of the tail rotary wheel;

the central hole of the rotating wheel (3) is circumferentially provided with anti-slip grooves (324), and the anti-slip protrusions (321) can be matched with the anti-slip grooves (324) mutually.

9. The limit switch structure based on the hall sensor and the magnet according to claim 1, wherein key grooves (322) are arranged on the middle rotary wheel locking ring (32) and the tail rotary wheel locking ring (33);

a plurality of locking keys (323) are uniformly arranged on the transmission shaft (1), and the locking keys (323) can be matched with key grooves on the middle rotary wheel locking ring (32) and key grooves on the tail rotary wheel locking ring (33).

10. A rotary limit switch, characterized in that the limit switch structure based on the hall sensor and the magnet as claimed in any one of claims 1-9 is adopted.