Safety Locking Prompt Device and Method for Lifting Arms of Two-Column Lifts

Abstract

The present invention provides a safety locking prompt device and method for a lifting arm of a two-column lift. The device includes a fixing component, an inductive proximity switch group, and a chip. The inductive proximity switch group is arranged on the fixing component. The inductive proximity switch group includes a plurality of inductive proximity switches. Each inductive proximity switch is respectively connected to an input pin of the chip. The chip is a NAND gate chip. The output pin of the chip is connected to an amplifying circuit, and an indicator is arranged on the amplifying circuit. The method includes: (1) signal induction; (2) signal collection and processing; (3) automatic control and prompt. Using the present invention, it avoids the misjudgment of the operator on the sound of the safety lock being locked, effectively prevents safety accidents such as unilateral locking and tipping of the lifting arm of the lift; reduces mechanical collision, improves the mechanical life; and has stable performance, accurate resolution, good sensitivity, fast response speed, and strong versatility.

Description

Technical Field

[0001] The present invention relates to the technical field of two-column lifts, and particularly to a safety locking prompt device and method for the lift arms of a lift. Background Art

[0002] Two-column lifts are special mechanical lifting equipment commonly used in automobile repair and maintenance units. As Figure 4 shown, the lift includes lift columns 21 of the lift, a lift slide 12 and lift arms. The lift arms are arranged on the lift slide 12 (not shown in the figure). The lift slide 12 can move up and down along the lift columns 21. A safety lock (also called a locking ratchet, not shown in the figure) is provided on the lift slide 12, and a plurality of safety locking strips 22 are provided on the lift columns 21. The safety lock can be interlocked with the safety locking strips 22 to lock the position of the lift slide 12. When using a two-column lift to lift a vehicle, after the lifting height reaches the working height, the operator should pay attention to the sound of the safety lock being locked. Generally, there are two sounds, and then the lift arms are slightly lowered to lock the safety lock firmly to lock the lift arms. This operating procedure has potential safety hazards: (1) Due to the influence of environmental noise, when the operator misjudges the sound of the safety lock being locked and performs the action of lowering the slide, it will cause one-sided lift arms to be locked, and the other lift arm will drop at least the distance of one safety locking strip, resulting in vehicle rollover and personal injury accidents; (2) If the operator does not hear the sound of the safety lock being locked, it will be difficult to determine whether the safety lock is locked. Continuing with the adjustment operation will cause the safety locking strip 23 to collide with the safety lock, and the hydraulic cylinder to receive excessive loads. Summary of the Invention

[0003] To solve the above technical problems, the present invention provides a safety locking prompt device and a prompt method for the lift arms of a two-column lift.

[0004] The present invention is achieved through the following technical solutions.

[0005] The present invention provides a safety locking prompt device for the lift arms of a two-column lift, including a fixing component, an inductive proximity switch group, and a chip. The inductive proximity switch group is arranged on the fixing component. The inductive proximity switch group includes a plurality of inductive proximity switches. Each inductive proximity switch is respectively connected to an input pin of the chip. The chip is a NAND gate chip, and an output pin of the chip is connected to an amplifier circuit, and an indicator is provided on the amplifier circuit.

[0006] The inductive proximity switch group includes inductive proximity switch 1, inductive proximity switch 2, and inductive proximity switch 3. The VCC terminals of inductive proximity switch 1, inductive proximity switch 2, and inductive proximity switch 3 are connected to the positive pole of the power supply, and the VSS terminals are connected to the negative pole of the power supply. The out terminal of inductive proximity switch 1 is connected to pin 3 of the chip, the out terminal of inductive proximity switch 2 is connected to pin 4 of the chip, and the out terminal of inductive proximity switch 3 is connected to pin 5 of the chip.

[0007] The chip is a CD4023 three-input NAND gate chip.

[0008] A resistor 1 is also connected between pin 3 of the chip and the positive pole of the power supply, a resistor 2 is also connected between pin 4 of the chip and the positive pole of the power supply, and a resistor 3 is also connected between pin 5 of the chip and the positive pole of the power supply.

[0009] The amplification circuit includes an NPN transistor, a relay coil, and a relay. One end of the relay coil is connected to the positive pole of the power supply, the other end is connected to the collector of the transistor, the base of the transistor is connected to pin 6 of the chip, and the emitter of the transistor is connected to the negative pole of the power supply. One end of the relay is connected to the positive pole of the power supply, the other end is connected to the positive pole of the indicator, and the negative pole of the indicator is connected to the negative pole of the power supply.

[0010] The amplification circuit also includes a diode, which is connected in parallel with the relay coil, and the negative pole of the diode is connected to the positive pole of the power supply.

[0011] The power supply is a 12V dry battery, which is arranged in a battery holder, and the positive pole of the battery holder is connected to the power switch.

[0012] The indicator is an indicator light.

[0013] The fixing component includes clamp A and clamp B. The notches of clamp A and clamp B face each other and are connected by bolts. A base is provided on clamp A, and the inductive proximity switch is fixed on the base.

[0014] The base is provided with the same number of mounting holes as the inductive proximity switches, and the uppermost and lowermost mounting holes are oblong holes.

[0015] The base is also provided with a housing. The housing is provided with an indicator mounting hole and a power switch mounting hole. The indicator is arranged in the indicator mounting hole, the power switch is arranged in the power switch mounting hole, and the PCB board, the battery holder, and the inductive proximity switch group are all arranged in the housing.

[0016] The present invention also provides a method for prompting the safety locking of the lifting arm of a two-column lift, including the following steps:

[0017] (1) Signal induction: multiple sensing points are set according to the distance between two adjacent safety card strips. The sensing points move up and down synchronously with the lift slide and send out sensing signals. When the sensing point coincides with the safety card strip, the sensing point sends out signal 1, otherwise the sensing point sends out signal 2. When the lift arm is in a safety locked state, all sensing points are within the range between the two adjacent safety card strips;

[0018] (2) Signal collection and processing: collect signals from all sensing points, perform centralized processing, and issue command signals. When any sensing point issues signal 1, command 1 is output; when all sensing points issue signal 2, command 2 is output.

[0019] (3) Automatic control prompt: when the output instruction is one, the prompt is issued; when the output instruction is two, the prompt is stopped.

[0020] The step (1) of setting the sensing points and sending the sensing signals is specifically as follows: an inductive proximity switch is set corresponding to each sensing point, and the inductive proximity switch is fixed on the lift slide after adjusting the position; when the inductive proximity switch is close to the safety positioning strip, metal induction occurs, and the inductive proximity switch outputs a low-level signal as signal one; when the inductive proximity switch is offset from the safety positioning strip, metal induction does not occur, and the inductive proximity switch outputs a high-level signal as signal two.

[0021] The signal collection and processing of step (2) is specifically as follows: the signal of each sensing point is connected to different pins of the chip respectively, and the chip is used to perform NAND gate logic judgment on the sensing signal. When any signal is a low-level signal, the chip outputs a high-level signal as instruction one; when all signals are high-level signals, the chip outputs a low-level signal as instruction two.

[0022] The step (3) specifically comprises: using an amplifier circuit to amplify the command signal, the amplifier circuit being used as the power supply of the indicator light, when the command signal is at a high level, the amplified voltage causes the indicator light to illuminate, and when the command signal is at a low level, the amplified voltage is still at a low level, and the indicator light does not illuminate.

[0023] The beneficial effects of the present invention are:

[0024] Using the present invention has the following advantages: (1) It avoids the misjudgment of the operator on the sound of the safety lock being locked, effectively preventing safety accidents such as unilateral locking of the lifting arm of the lift and tipping over; (2) It reduces mechanical collisions and improves the mechanical life; (3) It does not modify the lift body and does not affect the safety performance indicators of the lift itself; (4) The judgment process of the safety locking of the lifting arm does not rely on movable contacts, with stable performance, accurate resolution, good sensitivity, and fast response speed; (5) It has strong versatility and can be applied to any two-post lift; (6) The circuit is simple, with low failure rate, convenient maintenance, and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic structural diagram of the present invention;

[0026] Figure 2 is a schematic diagram after the assembly of the present invention;

[0027] Figure 3 is a schematic circuit diagram of the present invention;

[0028] Figure 4 is a schematic diagram of the positional relationship between the column and the sliding table of a two-post lift in the prior art.

[0029] In the figure: 1 - base; 2 - battery; 3 - PCB board; 4 - battery holder; 5 - inductive proximity switch group; 6 - housing; 7 - indicator mounting hole; 8 - indicator; 9 - power switch mounting hole; 10 - power switch; 11 - clamp A; 12 - lift sliding table; 13 - clamp B; IC1 - chip; Q1 - triode; L1 - relay coil; K1 - relay; D1 - diode; B1 - inductive proximity switch one; B2 - inductive proximity switch two; B3 - inductive proximity switch three; R1 - resistor one; R2 - resistor two; R3 - resistor three; 21 - lift column; 22 - safety clamping strip. DETAILED DESCRIPTION OF THE INVENTION

[0030] The technical solution of the present invention will be further described below, but the scope of protection claimed is not limited thereto.

[0031] As Figures 1 to 3 is a schematic structural diagram of the present invention:

[0032] The present invention provides a safety locking prompt device for the lifting arm of a two-post lift, including a fixed component, an inductive proximity switch group 5, and a chip IC1. The inductive proximity switch group 5 is arranged on the fixed component. The inductive proximity switch group 5 includes a plurality of inductive proximity switches, and each inductive proximity switch is respectively connected to an input pin of the chip IC1. The chip IC1 is a NAND gate chip IC1, and the output pin of the chip IC1 is connected to an amplifier circuit, and an indicator 8 is arranged on the amplifier circuit.

[0033] During assembly, it is installed on the lifting machine slide 12 through the fixing component. First, adjust the lifting machine slide 12 to the safety locking position, and then adjust the horizontal position of the inductive proximity switch so that the horizontal distance between the inductive proximity switch and the safety clamping strip 22 is the set action distance. The horizontal distance between the inductive proximity switch and the safety clamping strip 22 should not be too close, so as to prevent the inductive proximity switch from still being able to sense the metal of the lifting machine column 21 when the inductive proximity switch and the safety clamping strip 22 are vertically misaligned. After adjusting the horizontal position of the inductive proximity switch, adjust its vertical position so that the inductive proximity switch is in the area between two adjacent safety clamping strips 22, and the sensing areas of the uppermost and lowermost inductive proximity switches are at the edges of the safety clamping strip 22. At this time, the inductive proximity switch is in the critical set action state, and finally, fix the inductive proximity switch group 5 with screws.

[0034] When the present invention works after assembly, the inductive proximity switch, the chip IC1, and the amplifier circuit are connected to the power supply for power supply. When the lifting arm of the lifting machine moves, any one of the inductive proximity switches detects the safety clamping strip 22 and outputs a low level, so that the NAND gate chip IC1 outputs a high level signal. The high level signal makes the indicator 8 energized to work and issue a prompt after passing through the amplifier circuit. Therefore, when the indicator 8 does not issue a prompt, it means that the lifting arm of the lifting machine is in the safety locking state.

[0035] In summary, adopting the present invention has the following advantages: (1) It avoids the misjudgment of the sound of the safety lock being locked by the operator, and effectively prevents safety accidents such as unilateral locking and tipping of the lifting arm of the lifting machine; (2) It reduces mechanical collisions and improves the mechanical life; (3) As an auxiliary device, the present invention does not make any changes to the lifting machine body and will not affect the safety performance indicators such as the rigidity and strength of the lifting machine; (4) The judgment process of the safety locking of the lifting arm does not rely on movable contacts, so it has stable performance, accurate resolution, good sensitivity, and fast response speed; (5) It has strong versatility and can be applied to any two-column lifting machine; (6) The circuit is simple, the failure rate is low, the maintenance is convenient, and the cost is low.

[0036] The inductive proximity switch group 5 includes the first inductive proximity switch B1, the second inductive proximity switch B2, and the third inductive proximity switch B3. The VCC terminals of the first inductive proximity switch B1, the second inductive proximity switch B2, and the third inductive proximity switch B3 are connected to the positive pole of the power supply, and the VSS terminals are connected to the negative pole of the power supply. The out terminal of the first inductive proximity switch B1 is connected to the 3rd pin of the chip IC1, the out terminal of the second inductive proximity switch B2 is connected to the 4th pin of the chip IC1, and the out terminal of the third inductive proximity switch B3 is connected to the 5th pin of the chip IC1. Using three inductive proximity switches can effectively prevent the situation of missed alarms caused by the upper and lower inductive proximity switches straddling the safety clamping strip 22 when the distance between the safety clamping strips 22 is large.

[0037] The chip IC1 is a CD4023 three-input NAND gate chip IC1. Using this chip IC1, the cost is low and the failure rate is low.

[0038] A resistor R1 is also connected between the 3-pin of the chip IC1 and the positive power supply, a resistor R2 is also connected between the 4-pin of the chip IC1 and the positive power supply, and a resistor R3 is also connected between the 5-pin of the chip IC1 and the positive power supply.

[0039] The amplification circuit includes an NPN transistor Q1, a relay coil L1, and a relay K1. One end of the relay coil L1 is connected to the positive power supply, the other end is connected to the collector of the transistor Q1, the base of the transistor Q1 is connected to the 6-pin of the chip IC1, the emitter of the transistor Q1 is connected to the negative power supply, one end of the relay K1 is connected to the positive power supply, the other end is connected to the positive pole of the indicator 8, and the negative pole of the indicator 8 is connected to the negative power supply.

[0040] The amplification circuit also includes a diode D1. The diode D1 is connected in parallel with the relay coil L1, and the negative pole of the diode D1 is connected to the positive power supply. When the transistor Q1 is turned off instantaneously, the diode D1 inherits the current of the relay coil L1, so that the current decays slowly to protect the transistor Q1 and prevent the voltage at the collector of the transistor Q1 from increasing suddenly.

[0041] It also includes a PCB board 3. The chip IC1, the amplification circuit, the resistor R1, the resistor R2, and the resistor R3 are arranged on the PCB board 3.

[0042] A power switch 10 is provided at the positive power supply. It is used to control the start and stop of the device. When not in use, the power supply is disconnected to protect the electrical components and save power.

[0043] The power supply is a 12V dry battery. The dry battery is arranged in the battery holder 4, and the positive pole of the battery holder 4 is connected to the power switch 10. This makes the power supply convenient.

[0044] The indicator 8 is an indicator light.

[0045] The fixing component includes a hoop A11 and a hoop B13. The notch of the hoop A11 and the hoop B13 are opposite to each other and are connected by bolts. A base 1 is provided on the hoop A11, and the inductive proximity switch is fixed on the base 1. The installation is convenient and easy to adjust.

[0046] The base 1 is provided with the same number of mounting holes as the inductive proximity switches. The uppermost and lowermost mounting holes are oblong holes, so that the sensing surfaces of the upper and lower inductive proximity switches can be more accurately aligned with the edge of the safety clamping strip 22. After alignment, they are fixed with screws.

[0047] A shell 6 is also provided on the base 1. An indicator mounting hole 7 and a power switch mounting hole 9 are provided on the shell 6, which are used to install an indicator 8 and a power switch 10 respectively, so as to facilitate power control and observation of the indicator 8; the PCB board 3, the battery holder 4, and the inductive proximity switch group 5 are all arranged in the shell 6, so as to facilitate component protection and space saving.

[0048] The present invention also provides a two-column lift arm safety locking prompting method, comprising the following steps:

[0049] (1) Signal induction: multiple sensing points are set according to the distance between two adjacent safety locking strips 22. The sensing points move up and down synchronously with the lift slide 12 and send out sensing signals. When the sensing point coincides with the safety locking strip 22, the sensing point sends out signal 1, otherwise the sensing point sends out signal 2. When the lift arm is in a safety locked state, all the sensing points are within the range between the two adjacent safety locking strips 22;

[0050] (2) Signal collection and processing: collect signals from all sensing points, perform centralized processing, and issue command signals. When any sensing point issues signal 1, command 1 is output; when all sensing points issue signal 2, command 2 is output.

[0051] (3) Automatic control prompt: when the output instruction is one, the prompt is issued; when the output instruction is two, the prompt is stopped.

[0052] The step (1) of setting the sensing point and sending the sensing signal is specifically as follows: an inductive proximity switch is set corresponding to each sensing point, and the inductive proximity switch is fixed on the lift slide 12 after adjusting the position. When the inductive proximity switch is close to the safety positioning strip 22, metal induction occurs and a low-level signal is output as signal one. When the inductive proximity switch is offset from the safety positioning strip 22, metal induction does not occur and a high-level signal is output as signal two.

[0053] The signal collection and processing of step (2) is specifically as follows: the signal of each sensing point is connected to different pins of chip IC1 respectively, and chip IC1 is used to perform NAND gate logic judgment on the sensing signal. When any signal is a low-level signal, chip IC1 outputs a high-level signal as instruction one; when all signals are high-level signals, chip IC1 outputs a low-level signal as instruction two.

[0054] Taking the setting of three inductive proximity switches as an example, the truth table of the NAND gate logic judgment is as follows: (In the table, A, B, C are the signals of the sensing point, and Y is the command signal)

[0055] A B C Y 0 0 0 1 0 0 1 1 0 1 0 1 0 1 1 1 1 0 0 1 1 0 1 1 1 1 0 1 1 1 1 0

[0056] The specific content of step (3) is as follows: an amplifier circuit is used to amplify and process the command signal. The amplifier circuit serves as the power supply for the indicator light. When the command signal is at a high level, the amplified voltage causes the indicator light to emit light. When the command signal is at a low level, the amplified voltage remains at a low level and the indicator light does not emit light.

[0057] By means of this method, it is possible to avoid the misjudgment of the sound generated by the locking of the safety lock by the operator, effectively prevent safety accidents such as unilateral locking of the lifting arm of the lift and tipping over, and reduce mechanical collisions and improve the mechanical service life.

Claims

1. A two-post lift arm safety locking reminder method, Features: The steps include: (1) Signal sensing, a plurality of sensing points are set according to the distance between two adjacent safety locking strips (22), and the sensing points move up and down synchronously with the lift slide (12) to send out sensing signals. When the sensing point coincides with the safety locking strip (22), the sensing point sends out signal one, otherwise the sensing point sends out signal two. When the lift arm is in a safety locking state, all the sensing points are within the range between the two adjacent safety locking strips (22); (2) Signal collection and processing: collect signals from all sensing points, perform centralized processing, and issue command signals. When any sensing point issues signal 1, command 1 is output; when all sensing points issue signal 2, command 2 is output. (3) Automatic control prompt: when the output instruction is one, the prompt is issued; when the output instruction is two, the prompt is stopped.

2. The two-post lift arm safety locking reminder method according to claim 1, Features: The step (1) of setting the sensing point and sending the sensing signal specifically comprises: setting an inductive proximity switch corresponding to each sensing point, and fixing the inductive proximity switch on the lift slide (12) after adjusting the position; when the inductive proximity switch approaches the safety positioning strip (22), metal induction occurs, and the inductive proximity switch outputs a low-level signal as signal one; when the inductive proximity switch is offset from the safety positioning strip (22), metal induction does not occur, and the inductive proximity switch outputs a high-level signal as signal two.

3. The two-post lift arm safety locking reminder method according to claim 1, Features: The signal collection and processing in step (2) is specifically as follows: the signal of each sensing point is connected to different pins of the chip (IC1) respectively, and the chip (IC1) is used to perform a NAND gate logic judgment on the sensing signal; when any signal is a low-level signal, the chip (IC1) outputs a high-level signal as instruction one; when all signals are high-level signals, the chip (IC1) outputs a low-level signal as instruction two.

4. The two-post lift arm safety locking prompting method according to claim 1, Features: The step (3) specifically comprises: using an amplifier circuit to amplify the command signal, the amplifier circuit being used as the power supply of the indicator light, when the command signal is at a high level, the amplified voltage causes the indicator light to illuminate, and when the command signal is at a low level, the amplified voltage is still at a low level, and the indicator light does not illuminate.

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