Electric lifting control circuit for spring pantograph

Abstract

The invention discloses an electric lifting control circuit for a spring pantograph, and belongs to the technical field of pantograph control. Comprising a pantograph rising control loop, a pantograph falling control loop, a pantograph rising in-place signal control loop and a pantograph falling in-place signal control loop. The pantograph rising control loop is used for executing a pantograph rising control method, so that during pantograph rising, the pantograph falling control loop is not switched on, and pantograph falling cannot be carried out; the pantograph descending control loop is used for executing a pantograph descending control method, so that during pantograph descending, the pantograph ascending control loop is not switched on, pantograph ascending cannot be achieved, and then pantograph ascending and descending interlocking is achieved; the pantograph rising in-place signal control loop is used for executing a pantograph rising in-place signal control method to obtain a pantograph rising in-place signal; and the pantograph descending in-place signal control loop is used for executing the pantograph descending in-place signal control method to obtain a pantograph descending in-place signal. According to the invention, pantograph lifting control and pantograph lifting signal control functions are integrated, so that the device is simpler; lifting bow interlocking control is achieved through hardware wiring, power supply short circuit is avoided, and higher safety is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of pantograph control, and in particular to a spring pantograph electric lifting control circuit. Background Art

[0002] Currently, most urban rail transit pantographs in China use pneumatic control for pantograph raising and lowering. This requires: 1. High-pressure air supply from the vehicle; 2. A pneumatic control valve plate control unit inside the vehicle or on the pantograph; 3. High-pressure piping; and 4. Pantograph status monitoring. This complex control system, involving both pneumatic and electrical controls, makes troubleshooting difficult. To simplify the control system and meet the requirements for eliminating pneumatic control on vehicles, an electric control circuit integrating pantograph control and pantograph status signals is required. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a spring pantograph electric lifting control circuit.

[0004] The object of the present invention is achieved through the following technical solutions: a spring pantograph electric lifting control circuit, comprising a pantograph raising control circuit, a pantograph lowering control circuit, a pantograph raising in place signal control circuit, and a pantograph lowering in place signal control circuit; The bow raising control circuit is used to execute the bow raising control method, so that when the bow is raised, the bow lowering control circuit is disconnected and the bow cannot be lowered; the bow lowering control circuit is used to execute the bow lowering control method, so that when the bow is lowered, the bow raising control circuit is disconnected and the bow cannot be raised, thereby achieving interlocking of bow raising and bow lowering; The bow raising position signal control circuit is used to execute the bow raising position signal control method to obtain the bow raising position signal; the bow lowering position signal control circuit is used to execute the bow lowering position signal control method to obtain the bow lowering position signal.

[0005] Preferably, the bow raising control circuit includes a bow raising button 1.1, the first end of the bow raising button 1.1 is connected to the positive power supply, the bow raising button 1.1 is connected in parallel with the normally open contact 1.2 of the bow raising relay K1, and the second end of the bow raising button 1.1 is connected to the coil 1.3 of the bow raising relay K1 and the coil 1.4 of the bow raising relay K2; the coil 1.3 of the bow raising relay K1 and the coil 1.4 of the bow raising relay K2 are connected in parallel, the coil 1.3 of the bow raising relay K1 and the coil of the bow raising relay K2 are connected to the normally closed contact 1.5 of the bow raising position magnetic switch S3; the normally closed contact 1.5 of the bow raising position magnetic switch S3 is connected to the normally closed contact 1.6 of the bow lowering relay K5; the normally closed contact 1.6 of the bow lowering relay K5 is connected to the negative power supply.

[0006] Preferably, the bow lowering control circuit includes a bow lowering button 2.1, a first end of the bow lowering button 2.1 is connected to a positive power supply, the bow lowering button 2.1 is connected in parallel with a normally open contact 2.2 of a bow lowering relay K4, and a second end of the bow lowering button 2.1 is connected to a coil 2.3 of the bow lowering relay K4 and a coil 2.4 of the bow lowering relay K5; the coil 2.3 of the bow lowering relay K4 and the coil 2.4 of the bow lowering relay K5 are connected in parallel, the coil 2.3 of the bow lowering relay K4 and the coil 2.4 of the bow lowering relay K5 are connected to a normally closed contact 2.5 of a bow lowering position magnetic switch S4; the normally closed contact 2.5 of the bow lowering position magnetic switch S4 is connected to a normally closed contact 2.6 of a bow raising relay K2; and the normally closed contact 2.6 of the bow raising relay K2 is connected to a negative power supply.

[0007] Preferably, the bow-raising-in-place signal control circuit includes a coil 3.1 of a bow-raising-in-place relay K3, the A1 end of the coil 3.1 of the bow-raising-in-place relay K3 is connected to a positive power supply, and the A2 end of the coil 3.1 of the bow-raising-in-place relay K3 is connected to a normally open contact 3.2 of a bow-raising-in-place magnetic switch S3; the normally open contact 3.2 of the bow-raising-in-place magnetic switch S3 is connected to a normally closed contact 1.6 of a bow-lowering relay K5; and the normally closed contact 1.6 of the bow-lowering relay K5 is connected to a negative power supply.

[0008] Preferably, the bow-lowering-in-place signal control circuit includes a coil 4.1 of a bow-lowering-in-place relay K6, an A1 end of the coil 4.1 of the bow-lowering-in-place relay K6 is connected to a positive power supply, and an A2 end of the coil 4.1 of the bow-lowering-in-place relay K6 is connected to a normally open contact 4.2 of a bow-lowering-in-place magnetic switch S4; the normally open contact 4.2 of the bow-lowering-in-place magnetic switch S4 is connected to a normally closed contact 2.6 of a bow-raising relay K2; and the normally closed contact 2.6 of the bow-raising relay K2 is connected to a negative power supply.

[0009] Preferably, the bow raising control method comprises the following steps: Press the pantograph raising button 1.1, and the coil 1.3 of the pantograph raising relay K1 and the coil 1.4 of the pantograph raising relay K2 are energized at the same time, and the contacts of the pantograph raising relay K1 and the pantograph raising relay K2 are closed; The motor reverses and the piston rod retracts the pantograph to raise the pantograph. At the same time, the normally open contact 1.2 of the pantograph raising relay K1 is closed to keep the motor running until the pantograph is raised into place. When the bow is raised to the full height, the normally closed contact 1.5 of the magnetic switch S3 is disconnected, the coil 1.3 of the bow raising relay K1 and the coil 1.4 of the bow raising relay K2 lose power, the bow raising relay K1 and the bow raising relay K2 reset, and the motor stops running; during the bow raising process, the bow raising relay K2 is closed, the normally closed contact 2.6 of the bow raising relay K2 is disconnected, the bow lowering control circuit is not connected, and the bow cannot be lowered.

[0010] Preferably, the bow lowering control method comprises the following steps: Press the pantograph lowering button 2.1, and the coil 2.3 of the pantograph lowering relay K4 and the coil 2.4 of the pantograph lowering relay K5 are energized at the same time, and the contacts of the pantograph lowering relay K4 and the pantograph lowering relay K5 are closed; The motor rotates forward and the piston rod pushes the pantograph down. At the same time, the normally open contact 2.2 of the pantograph lowering relay K4 is closed to keep the motor running until the pantograph is lowered into place. When the pantograph is lowered, the normally closed contact 2.5 of the magnetic switch S4 is disconnected, the coil 2.3 of the pantograph lowering relay K4 and the coil 2.4 of the pantograph lowering relay K5 lose power, the pantograph lowering relay K4 and the pantograph lowering relay K5 reset, and the motor stops running; during the pantograph lowering process, the pantograph lowering relay K5 is closed, the normally closed contact 1.6 of the pantograph lowering relay K5 is disconnected, the pantograph raising control circuit is not connected, and the pantograph cannot be raised.

[0011] Preferably, the bow raising signal control method includes the following steps: After the bow is raised into place, the normally open contact 3.2 of the bow-raised into place magnetic switch S3 is closed, the coil 3.1 of the bow-raised into place relay K3 is energized, the contacts of the bow-raised into place relay K3 are closed, and the bow-raised into place relay K3 gives a bow-raised into place signal.

[0012] Preferably, the method for controlling the pantograph in-position signal comprises the following steps: After the pantograph is in place, the normally open contact 4.2 of the pantograph-in-place magnetic switch S4 is closed, the coil 4.1 of the pantograph-in-place relay K6 is energized, the contacts of the pantograph-in-place relay K6 are closed, and the pantograph-in-place relay K6 gives a pantograph-in-place signal.

[0013] The beneficial effects of the present invention are: 1) It integrates the functions of pantograph control and pantograph signal control, making it simpler. The pantograph interlocking control is achieved through hardware wiring to avoid power short circuit, which is safer. The pantograph is automatically stopped and a signal is sent through the pantograph in place magnetic switches S3 and S4, and self-locking is achieved through the normally open contacts of the pantograph relays K1 and K4. The pantograph button only needs to provide a pulse signal to achieve continuous pantograph raising. The vehicle end can save the pantograph delay relay, saving costs and being more economical. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is the schematic diagram of the spring pantograph electric lifting control circuit. DETAILED DESCRIPTION

[0015] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work shall fall within the scope of protection of the present invention.

[0016] See Figure 1 The present invention provides a technical solution: a spring pantograph electric lifting control circuit, including a pantograph raising control circuit, a pantograph lowering control circuit, a pantograph raising in place signal control circuit and a pantograph lowering in place signal control circuit; The bow raising control circuit is used to execute the bow raising control method, so that when the bow is raised, the bow lowering control circuit is disconnected and the bow cannot be lowered; the bow lowering control circuit is used to execute the bow lowering control method, so that when the bow is lowered, the bow raising control circuit is disconnected and the bow cannot be raised, thereby achieving interlocking of bow raising and bow lowering; The bow raising position signal control circuit is used to execute the bow raising position signal control method to obtain the bow raising position signal; the bow lowering position signal control circuit is used to execute the bow lowering position signal control method to obtain the bow lowering position signal.

[0017] In some embodiments, the bow raising control circuit includes a bow raising button 1.1, the first end of the bow raising button 1.1 is connected to a positive power supply, the bow raising button 1.1 is connected in parallel with a normally open contact 1.2 of a bow raising relay K1, and the second end of the bow raising button 1.1 is connected to a coil 1.3 of the bow raising relay K1 and a coil 1.4 of the bow raising relay K2; the coil 1.3 of the bow raising relay K1 and the coil 1.4 of the bow raising relay K2 are connected in parallel, the coil 1.3 of the bow raising relay K1 and the coil of the bow raising relay K2 are connected to a normally closed contact 1.5 of a bow raising position magnetic switch S3; the normally closed contact 1.5 of the bow raising position magnetic switch S3 is connected to a normally closed contact 1.6 of a bow lowering relay K5; the normally closed contact 1.6 of the bow lowering relay K5 is connected to a negative power supply.

[0018] In this embodiment, the current flow of the bow-raising control loop is: +110V→1.1 and 1.2 in parallel→1.3 and 1.4 in parallel→1.5→1.6→0V.

[0019] In some embodiments, the bow lowering control circuit includes a bow lowering button 2.1, a first end of the bow lowering button 2.1 is connected to a positive power supply, the bow lowering button 2.1 is connected in parallel with a normally open contact 2.2 of a bow lowering relay K4, and a second end of the bow lowering button 2.1 is connected to a coil 2.3 of the bow lowering relay K4 and a coil 2.4 of the bow lowering relay K5; the coil 2.3 of the bow lowering relay K4 and the coil 2.4 of the bow lowering relay K5 are connected in parallel, the coil 2.3 of the bow lowering relay K4 and the coil 2.4 of the bow lowering relay K5 are connected to a normally closed contact 2.5 of a bow lowering position magnetic switch S4; the normally closed contact 2.5 of the bow lowering position magnetic switch S4 is connected to a normally closed contact 2.6 of a bow raising relay K2; the normally closed contact 2.6 of the bow raising relay K2 is connected to a negative power supply.

[0020] In this embodiment, the current flow of the pantograph lowering control circuit is: +110V→2.1 and 2.2 in parallel→2.3 and 2.4 in parallel→2.5→2.6→0V.

[0021] In some embodiments, the bow-raising-in-place signal control circuit includes a coil 3.1 of a bow-raising-in-place relay K3, wherein the A1 end of the coil 3.1 of the bow-raising-in-place relay K3 is connected to a positive power supply, and the A2 end of the coil 3.1 of the bow-raising-in-place relay K3 is connected to a normally open contact 3.2 of a bow-raising-in-place magnetic switch S3; the normally open contact 3.2 of the bow-raising-in-place magnetic switch S3 is connected to a normally closed contact 1.6 of a bow-lowering relay K5; and the normally closed contact 1.6 of the bow-lowering relay K5 is connected to a negative power supply.

[0022] In this embodiment, the current flow direction of the bow-raising position signal control loop is: +110V→3.1→3.2→1.6→0V.

[0023] In some embodiments, the bow-lowering-in-place signal control circuit includes a coil 4.1 of a bow-lowering-in-place relay K6, wherein the A1 end of the coil 4.1 of the bow-lowering-in-place relay K6 is connected to a positive power supply, and the A2 end of the coil 4.1 of the bow-lowering-in-place relay K6 is connected to a normally open contact 4.2 of a bow-lowering-in-place magnetic switch S4; the normally open contact 4.2 of the bow-lowering-in-place magnetic switch S4 is connected to a normally closed contact 2.6 of a bow-raising relay K2; and the normally closed contact 2.6 of the bow-raising relay K2 is connected to a negative power supply.

[0024] In this embodiment, the current flow direction of the pantograph-lowering-position signal control loop is: +110V→4.1→4.2→2.6→0V.

[0025] In some embodiments, the bow raising control method includes the following steps: Press the pantograph raising button 1.1, and the coil 1.3 of the pantograph raising relay K1 and the coil 1.4 of the pantograph raising relay K2 are energized at the same time, and the contacts of the pantograph raising relay K1 and the pantograph raising relay K2 are closed; The motor reverses and the piston rod retracts the pantograph to raise the pantograph. At the same time, the normally open contact 1.2 of the pantograph raising relay K1 is closed to keep the motor running until the pantograph is raised into place. When the bow is raised to the full height, the normally closed contact 1.5 of the magnetic switch S3 is disconnected, the coil 1.3 of the bow raising relay K1 and the coil 1.4 of the bow raising relay K2 lose power, the bow raising relay K1 and the bow raising relay K2 reset, and the motor stops running; during the bow raising process, the bow raising relay K2 is closed, the normally closed contact 2.6 of the bow raising relay K2 is disconnected, the bow lowering control circuit is not connected, and the bow cannot be lowered.

[0026] In this embodiment, the pantograph raising control operates as follows: Press 1.1 → 1.3 and 1.4 are energized simultaneously → K1 and K2 contacts close → the motor reverses, retracting the piston rod to raise the pantograph while 1.2 engages to keep the motor running → the pantograph is fully raised → 1.5 is disconnected → 1.3 and 1.4 are de-energized → K1 and K2 reset → the motor stops. During the pantograph raising process, K2 closes and 2.6 opens, preventing the pantograph from being lowered, thus achieving pantograph raising and lowering interlocking.

[0027] In some embodiments, the bow lowering control method includes the following steps: Press the pantograph lowering button 2.1, and the coil 2.3 of the pantograph lowering relay K4 and the coil 2.4 of the pantograph lowering relay K5 are energized at the same time, and the contacts of the pantograph lowering relay K4 and the pantograph lowering relay K5 are closed; The motor rotates forward and the piston rod pushes the pantograph down. At the same time, the normally open contact 2.2 of the pantograph lowering relay K4 is closed to keep the motor running until the pantograph is lowered into place. When the pantograph is lowered, the normally closed contact 2.5 of the magnetic switch S4 is disconnected, the coil 2.3 of the pantograph lowering relay K4 and the coil 2.4 of the pantograph lowering relay K5 lose power, the pantograph lowering relay K4 and the pantograph lowering relay K5 reset, and the motor stops running; during the pantograph lowering process, the pantograph lowering relay K5 is closed, the normally closed contact 1.6 of the pantograph lowering relay K5 is disconnected, the pantograph raising control circuit is not connected, and the pantograph cannot be raised.

[0028] In this embodiment, the pantograph lowering control operates as follows: Press 2.1 → 2.3 and 2.4 are energized simultaneously → K4 and K5 contacts close → the motor rotates forward, pushing the piston rod to lower the pantograph while 2.2 is engaged to keep the motor running → the pantograph is fully lowered → 2.5 is disconnected → 2.3 and 2.4 are de-energized → K4 and K5 are reset → the motor stops. During the pantograph lowering process, K5 is closed and 1.6 is disconnected, preventing the pantograph from being raised, thus achieving pantograph raising and lowering interlocking.

[0029] In some embodiments, the method for controlling the bow-in-position signal comprises the following steps: After the bow is raised into place, the normally open contact 3.2 of the bow-raised into place magnetic switch S3 is closed, the coil 3.1 of the bow-raised into place relay K3 is energized, the contacts of the bow-raised into place relay K3 are closed, and the bow-raised into place relay K3 gives a bow-raised into place signal.

[0030] In this embodiment, the working principle of the pantograph in place signal control circuit is: pantograph in place → 3.2 closed → 3.1 energized → K3 contact closed → 11-14 of K3 gives pantograph in place signal.

[0031] In some embodiments, the method for controlling the pantograph in position signal comprises the following steps: After the pantograph is in place, the normally open contact 4.2 of the pantograph-in-place magnetic switch S4 is closed, the coil 4.1 of the pantograph-in-place relay K6 is energized, the contacts of the pantograph-in-place relay K6 are closed, and the pantograph-in-place relay K6 gives a pantograph-in-place signal.

[0032] In this embodiment, the working principle of the pantograph lowering signal control circuit is: pantograph lowering is in place → 4.2 is closed → 4.1 is energized → K6 contact is closed → 11-14 of K6 gives the pantograph lowering signal.

[0033] The foregoing description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Rather, the present invention can be used in various other combinations, modifications, and environments and can be modified within the scope of the concept described herein through the above teachings or techniques or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be protected by the appended claims.

Claims

1. A spring pantograph electric lifting control circuit, characterized by: It includes a pantograph raising control circuit, a pantograph lowering control circuit, a pantograph raising position signal control circuit and a pantograph lowering position signal control circuit; The bow raising control circuit is used to execute the bow raising control method, so that when the bow is raised, the bow lowering control circuit is disconnected and the bow cannot be lowered; the bow lowering control circuit is used to execute the bow lowering control method, so that when the bow is lowered, the bow raising control circuit is disconnected and the bow cannot be raised, thereby achieving interlocking of bow raising and bow lowering; The bow raising position signal control circuit is used to execute the bow raising position signal control method to obtain the bow raising position signal; the bow lowering position signal control circuit is used to execute the bow lowering position signal control method to obtain the bow lowering position signal.

2. The spring pantograph electric lifting control circuit according to claim 1, characterized in that: The bow raising control circuit includes a bow raising button 1.1, a first end of which is connected to a positive power supply, a normally open contact 1.2 of a bow raising relay K1 is connected in parallel to the bow raising button 1.1, and a second end of the bow raising button 1.1 is connected to a coil 1.3 of the bow raising relay K1 and a coil 1.4 of the bow raising relay K2; the coil 1.3 of the bow raising relay K1 and the coil 1.4 of the bow raising relay K2 are connected in parallel, the coil 1.3 of the bow raising relay K1 and the coil of the bow raising relay K2 are connected to a normally closed contact 1.5 of a bow raising position magnetic switch S3; the normally closed contact 1.5 of the bow raising position magnetic switch S3 is connected to a normally closed contact 1.6 of a bow lowering relay K5; and the normally closed contact 1.6 of the bow lowering relay K5 is connected to a negative power supply.

3. The spring pantograph electric lifting control circuit according to claim 1, characterized in that: The bow lowering control circuit includes a bow lowering button 2.1, a first end of which is connected to a positive power supply, a normally open contact 2.2 of a bow lowering relay K4 is connected in parallel to the bow lowering button 2.1, and a second end of the bow lowering button 2.1 is connected to a coil 2.3 of the bow lowering relay K4 and a coil 2.4 of the bow lowering relay K5; the coil 2.3 of the bow lowering relay K4 and the coil 2.4 of the bow lowering relay K5 are connected in parallel, the coil 2.3 of the bow lowering relay K4 and the coil 2.4 of the bow lowering relay K5 are connected to a normally closed contact 2.5 of a bow lowering magnetic switch S4; the normally closed contact 2.5 of the bow lowering magnetic switch S4 is connected to a normally closed contact 2.6 of a bow raising relay K2; and the normally closed contact 2.6 of the bow raising relay K2 is connected to a negative power supply.

4. The spring pantograph electric lifting control circuit according to claim 1, characterized in that: The bow-raising signal control circuit includes a coil 3.1 of a bow-raising relay K3, wherein the A1 end of the coil 3.1 of the bow-raising relay K3 is connected to a positive power supply, and the A2 end of the coil 3.1 of the bow-raising relay K3 is connected to a normally open contact 3.2 of a bow-raising magnetic switch S3; the normally open contact 3.2 of the bow-raising magnetic switch S3 is connected to a normally closed contact 1.6 of a bow-lowering relay K5; and the normally closed contact 1.6 of the bow-lowering relay K5 is connected to a negative power supply.

5. The spring pantograph electric lifting control circuit according to claim 1, characterized in that: The bow-lowering-in-place signal control circuit includes a coil 4.1 of a bow-lowering-in-place relay K6, wherein the A1 end of the coil 4.1 of the bow-lowering-in-place relay K6 is connected to a positive power supply, and the A2 end of the coil 4.1 of the bow-lowering-in-place relay K6 is connected to a normally open contact 4.2 of a bow-lowering-in-place magnetic switch S4; the normally open contact 4.2 of the bow-lowering-in-place magnetic switch S4 is connected to a normally closed contact 2.6 of a bow-raising relay K2; and the normally closed contact 2.6 of the bow-raising relay K2 is connected to a negative power supply.

6. The spring pantograph electric lifting control circuit according to claim 1, characterized in that: The bow raising control method comprises the following steps: Press the pantograph raising button 1.1, and the coil 1.3 of the pantograph raising relay K1 and the coil 1.4 of the pantograph raising relay K2 are energized at the same time, and the contacts of the pantograph raising relay K1 and the pantograph raising relay K2 are closed; The motor reverses and the piston rod retracts the pantograph to raise the pantograph. At the same time, the normally open contact 1.2 of the pantograph raising relay K1 is closed to keep the motor running until the pantograph is raised into place. When the bow is raised to the full height, the normally closed contact 1.5 of the magnetic switch S3 is disconnected, the coil 1.3 of the bow raising relay K1 and the coil 1.4 of the bow raising relay K2 lose power, the bow raising relay K1 and the bow raising relay K2 reset, and the motor stops running; during the bow raising process, the bow raising relay K2 is closed, the normally closed contact 2.6 of the bow raising relay K2 is disconnected, the bow lowering control circuit is not connected, and the bow cannot be lowered.

7. The spring pantograph electric lifting control circuit according to claim 1, characterized in that: The bow lowering control method comprises the following steps: Press the pantograph lowering button 2.1, and the coil 2.3 of the pantograph lowering relay K4 and the coil 2.4 of the pantograph lowering relay K5 are energized at the same time, and the contacts of the pantograph lowering relay K4 and the pantograph lowering relay K5 are closed; The motor rotates forward and the piston rod pushes the pantograph down. At the same time, the normally open contact 2.2 of the pantograph lowering relay K4 is closed to keep the motor running until the pantograph is lowered into place. When the pantograph is lowered, the normally closed contact 2.5 of the magnetic switch S4 is disconnected, the coil 2.3 of the pantograph lowering relay K4 and the coil 2.4 of the pantograph lowering relay K5 lose power, the pantograph lowering relay K4 and the pantograph lowering relay K5 reset, and the motor stops running; during the pantograph lowering process, the pantograph lowering relay K5 is closed, the normally closed contact 1.6 of the pantograph lowering relay K5 is disconnected, the pantograph raising control circuit is not connected, and the pantograph cannot be raised.

8. The spring pantograph electric lifting control circuit according to claim 1, characterized in that: The method for controlling the bow raising position signal comprises the following steps: After the bow is raised into place, the normally open contact 3.2 of the bow-raised into place magnetic switch S3 is closed, the coil 3.1 of the bow-raised into place relay K3 is energized, the contacts of the bow-raised into place relay K3 are closed, and the bow-raised into place relay K3 gives a bow-raised into place signal.

9. The spring pantograph electric lifting control circuit according to claim 1, characterized in that: The method for controlling the pantograph in-position signal comprises the following steps: After the pantograph is in place, the normally open contact 4.2 of the pantograph-in-place magnetic switch S4 is closed, the coil 4.1 of the pantograph-in-place relay K6 is energized, the contacts of the pantograph-in-place relay K6 are closed, and the pantograph-in-place relay K6 gives a pantograph-in-place signal.

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