CS252960B1 - Special motor vehicle's auxiliary drive's gear shifting blocking device - Google Patents

Description

A device for blocking the shifting of the auxiliary drive of a purpose-built motor vehicle, the object of which is to prevent unprofessional engagement of the auxiliary drive and undesirable long-term overloading of the superstructure aggregates driven by the auxiliary drive. with air cylinder and electrical wiring with switch box through the parking brake control switch which is connected to the air pipe with the spring brake cylinder, and an air switch is connected to the air pipe between the electro-pneumatic distributor and the air cylinder and to the air pipe between the control the parking brake element and spring brake cylinder connected by its control roller to an electric pressure switch and the ignition switch is connected between the air switch and the clutch of the vehicle, the control switch is connected to one terminal of the switch directly to the air, and the clutch switch of the vehicle through the diode, the second terminal through the electro-pneumatic terminals of the power distributor, and the pressure switch to the vehicle.

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SUMMARY OF THE INVENTION The present invention provides a device for blocking the shifting of an auxiliary drive of a purpose-built motor vehicle, the purpose of which is to prevent unprofessional engagement of the auxiliary drive and undesirable long-term overloading of superstructure units driven by the auxiliary drive.

On special-purpose motor vehicles, in most cases of use, the power required to power the superstructure units taken from the auxiliary drive terminal of the special-purpose motor vehicle chassis is so small that the idle engine speed of the chassis engine is sufficient. In this case, the special-purpose superstructure units of the motor vehicle operate at their nominal speed at the idling speed of the chassis of the special-purpose motor vehicle, which is practically advantageous in terms of fuel consumption. The power take-off is operated electropneumatically, from the driver's seat and is possible when the main clutch is engaged and disengaged, and when the vehicle is stationary or moving, which is sufficient for some vehicles. The auxiliary drive engagement is indicated by a warning light on the instrument panel. If the operator of the vehicle in question does not accidentally disengage the main clutch of the vehicle or disengage the power take-off and engage the vehicle or engage the power take-off, the power take-off shifting occurs or serious damage occurs after some time; destruction of superstructure aggregates by long-term excessive increase of their speed.

The above-mentioned disadvantages are eliminated by a device for blocking the auxiliary drive of the purpose-built motor vehicle with an electro-pneumatic auxiliary drive, consisting of an electro-pneumatic distributor which is connected via an air line to an air cylinder and a switchgear wiring via a control switch The air duct is connected to an air duct between an electric pneumatic distributor and an air cylinder by means of an air switch connected by its actuating roller and to the air duct between a parking brake actuator and a spring-mounted brake cylinder connected by its control switch is electric pressure switch, the switch box is connected between the air switch and the vehicle clutch switch, the control switch is connected with one clamp on the a direct switch to the vehicle clutch switch via a diode and a second terminal via the electropneumatic switchgear and electrical pressure switch terminals to the vehicle body.

An advantage of the solution according to the invention is that the auxiliary drive can only be engaged if the vehicle is secured by the parking brake and at the same time the vehicle clutch is disengaged, and the auxiliary drive disengages separately when the vehicle is released.

BRIEF DESCRIPTION OF THE DRAWINGS The attached drawing is a diagram of a device for blocking the shifting of an auxiliary drive of a purpose-built motor vehicle according to the invention. The electropneumatic distributor 3 is connected via air duct to the air cylinder 1 and the electric distribution box with the switch box 9 via the control switch 8, the parking brake control element 2 is connected via air duct to the spring brake cylinder 4, connected by its control cam to the air switch B and to the air duct between the parking brake actuator 2 and the spring brake cylinder 4 is connected by its control roller to an electric pressure switch 5, the switch box 9 being connected between the air switch 6 and the clutch switch 7, the control switch 8 is connected by one terminal to the air switch 6 directly and to the vehicle clutch switch 7 via the diode 10 and the other terminal via the terminals of the electro-pneumatic distributor 3 and the electrical pressure switch 5 to the vehicle body. The compressed air is supplied via the electro-pneumatic distributor 3 directly to the air cylinder 1 via an air duct. The control voltage from the switch box 9 is applied between the air switch 6 and the vehicle clutch switch 7, if it is applied when the air switch 6 contacts are switched directly to the control switch terminal 8 or when the clutch switch 7 contacts are switched via diode 10 to the same terminal. control switch 8, when the contacts of control switch 8 are closed, control voltage is fed to the auxiliary drive ON indicator lamp terminal 11 and the electropneumatic switchgear terminal 3, the other terminal of which is connected to the auxiliary drive ON indicator terminal terminal 11 and to the vehicle . The parking brake control element 2 supplies compressed air through the air duct to the spring brake cylinder 4, which controls the parking brake of the purpose-built motor vehicle. When the vehicle is braked, the air duct that connects the parking brake control 2 and the spring brake cylinder 4 is depressurized and the electrical switch contacts 5 are closed. When the vehicle main clutch is disengaged, the contacts of the vehicle clutch switch 7 are closed. When the switch box 9 is switched on, after actuation of the control switch 8, the electro-pneumatic distributor 3 is adjusted so that the compressed air passes into the air cylinder 1 and the auxiliary drive is engaged. At that time, the air duct connecting the electro-pneumatic distributor 3 and the air cylinder 1 are already under pressure and the contacts of the air switch 8 'are ^1.

With the switch on, i.e. even after the main clutch of the vehicle is engaged, when the contacts of the vehicle clutch switch 7 are opened, a voltage supply to the terminal of the electro-pneumatic distributor 3 is provided via the air switch contacts fi. The auxiliary drive can be deactivated by switching off the control switch 8, when the air cylinder 1 is vented via the electro-pneumatic distributor 3. If the vehicle is released, with the auxiliary drive already engaged, by adjusting the parking brake control 2, compressed air is supplied through the air line to the spring brake cylinder 4 and the air line connecting the parking brake actuator 2 to the spring brake cylinder 4 is pressurized and electric. The pressure switch 5 is brought into the open position, thereby breaking the electrical circuit of the coil of the electro-pneumatic distributor 3, which in its resting position ensures the connection of the air cylinder 1 with the atmosphere. Similarly, it is not possible to supply voltage to the electro-pneumatic switchgear 3, unless the auxiliary drive has been engaged yet, with the vehicle main clutch engaged, when the contacts of the vehicle clutch switch 7 are opened. This is not possible to engage the power take-off when the main clutch is engaged and also to prevent serious damage or destruction of the superstructure units by overloading them at high speeds in all realistic modes of operation of the special-purpose vehicle.

Claims (1)

SUBJECT Apparatus for blocking the auxiliary drive of a special-purpose motor vehicle with an electro-pneumatic auxiliary transmission, consisting of an electrical pneumatic distributor which is connected via an air line to an air cylinder and a switchgear wiring via a control switch controlling the parking brake control element connected to a spring brake cylinder, characterized in that an air switch (6) is connected to the air duct between the electro-pneumatic distributor (3j and the air cylinder (1)) and an air duct between the parking brake control element (2) and the spring brake cylinder (4) is connected by its actuating roller to an electric pressure switch (5), the switch box (9) being connected between the air switch (6) and the vehicle clutch switch (7), the control switch (8) being connected by one terminal to the air switch (6) at and to the vehicle clutch switch (7) via the diode (10J) and the other terminal via the electropneumatic switchgear (3) and electrical pressure switch (5) terminals to the vehicle chassis.