DE1078873B - Overload shutdown device for engines with speed governors, especially for internal combustion engines - Google Patents

Description

GERMAN

In internal combustion engines, the torque (load) is usually through a filling block of the fuel supply element (e.g. in diesel engines on the control rod of the injection pump). Nevertheless, damage can occur in certain cases. This is explained in more detail below.

A malfunction, e.g. B. a major bearing damage, occur, which leads to an increase in performance. Damage can also occur to the drive motor itself, e.g. B. a piston seizure. In both cases, the drive motor controller will respond, more fuel and increase the torque until the blocked maximum filling is reached. If this increase in output is not enough, the engine will be shut down. chokes, d. That is, it decreases with the speed until it comes to a standstill. So the engine provides its for a longer period of time full strength to overcome the inhibition. A small mistake can result in a very Major damage occurs if the fault is not noticed in good time and the system is shut down quickly will. This process is particularly common with cylinder engines and multi-engine systems dangerous, as there is a ~ large power reserve.

The invention aims to create an automatic parking device that is used in a larger Load the engine immediately after the start of the devi; gens responds quickly to avoid secondary damage ve-reduce.

is is a safety device for power machines known, in which the movement of the regulator-operated fuel control element limiting The stop can be adjusted as a function of the torque output as well as the machine speed is and in which when the Kraftstoffre i'elgliedes is in contact with this stop by closing a S ". Omkreises and pressing one

Electromagnet

ei e lock is released, so that the force ei.jier released spring on the fuel control member acts in the parking sense.

Also known is a speed control device for injection internal combustion engines with an adjusting member which responds to changes in the speed of the internal combustion engine and acts on the flow rate control member of the injection pump, the Wp ι of which is limited in one direction of movement by a maximum amount stop, which by arbitrary intervention overcoming flexible K- Is adjustable, the resilient force acting in one direction acting on a stop housed in the controller housing itself, which acts directly on the lever forming the full-load stop for the adjusting member of the controller.

In contrast, the invention has the task of overload shutdown device
for power machines with speed governor,
especially for internal combustion engines

Applicant:

Motorenfabrik Darmstadt GmbH,
Darmstadt

Dipl.-Ing. Kurt Mangelsdorf, Darmstadt,
has been named as the inventor

found an overload shutdown device for prime movers to create that does not always respond to brief overload and by loosening a lock causes the release of the parking mechanism. In addition, one should use simple means working device can be created which is easily adaptable to all occurring operating conditions is.

It has already been proposed to stop the full load limit of the fuel supply element to arrange a limit switch, which an electrical when touching the regulating linkage There is contact and triggers a shutdown device. But if you are already driving under full load, you would this switch even with short load surges, controller fluctuations and easy regulation respond and switch off the engine. The installation of a delay relay would not be sufficient because driving at the blockage could not be differentiated from a real overload and would then turn off the engine in an undesirable manner. The circuit therefore became a shutdown facility guided via a contact in the drive lever, so that the circuit when the drive lever is operated is interrupted.

According to the present invention, it is proposed, in addition, a special elastic blocking to be provided in the regulating linkage, which in its initial position is a normal full load limitation and only after overcoming a spring preload releases the switching contact mentioned for the shutdown.

As is well known, the sleeve force and thus the force on the motor decreases with all speed governors when stalling Regulating linkage too tight, d. In other words, the further the speed drops below the set full load speed

909 · 768/133

is, the greater the contact pressure of the regulating rod on the stop. So the pressing force is a measure of the under-speed when stalling and thus also for the overload. According to the invention this regulator property is used and the full load blocking of the filling is elastic a pretensioned spring executed, which only when a minimum contact pressure is exceeded des -Reguliergestänges yields and then have an elek regulator with such a characteristic that when stalling, the sleeve force increases with decreasing speed; this is e.g. B. with all centrifugal levellers the case. The application is not limited to internal combustion engines, but also to Water and steam engines possible.

For drives with frequently occurring harmless overloads and stalling, such as with Excavators and bulldozers are the parking facility

Irish contact for the actuation of the switch 10 naturally not applicable accordingly. You can release it. In the event of controller fluctuations and slight ■> - ■ · ■■ - .. - ...

The contact cannot respond to regulation playing, as is the case with the known institutions the case is.

This is to be described in more detail below using an exemplary embodiment.

Fig. 1 shows an injection pump with regulator and the elastic blocking and Fig. 2 shows two diagrams for this.

With 1 (Fig. 1) the injection pump of a diesel engine is referred to, in which the attached centrifugal governor 2 pushes the control rod 3 of the pump back and forth, whereby the amount of fuel to be injected is regulated according to the load. The elastic blocking is attached to the left, at the free end of the control rod. In a housing 4, a compression spring 6 presses under bias on a displaceable spring plate 5, which carries a pin 7 leading out of the housing to the left to actuate an electrical contact 8. When the load increases (Fig. 2, position a), the controller pushes the control rod to the left to give more fuel. At full load b the control rod 3 comes to rest against the spring plate 5 and is held in place by the compression spring 6 which is under tension. In the event of an overload, the engine stalls (see c in FIG. 2), because the injection pump no longer supplies fuel due to the blockage. When the speed drops, the sleeve force on the controller and thus also the contact pressure of the control rod on the spring plate increases (see d). After a certain drop in speed, the preload of the compression spring is finally overcome (see at e); the spring plate gives way (see i), and the pin immediately activates the electrical contact (see g), which triggers the shutdown.

In order to ensure a quick response even with a slight drop in speed, the preload of the compression spring should be chosen as weak as possible, but on the other hand it must also be large enough to avoid a response even when the speed fluctuates. In order to prevent a significant excess amount of fuel from being conveyed when the spring plate yields, which is very desirable, the path to contact must be very short; if necessary, a leverage must be installed. From these requirements, a precise adjustment is necessary, which is why it is proposed that the bias of the locking spring z. B. by means of

ever

_trotzc i _m j _{t em} advantage be used when addressing the spring only at very low speed and can be solved only the coupling of the drive, .so that the engine is automatically intercepted shortly before the stopping.

Claims (5)

Patent claims: 1. Overload shutdown device for engines with speed governors, especially for internal combustion engines, in those in the linkage for the filling regulation an elastic, under tension full-load blocking by a spring is installed, characterized in that that the full load blocking only in the event of an overload with a certain drop in speed as a result of increasing Sleeve force of the controller (2) and thus increasing force in the regulating linkage (3) gives way and in a known manner Contact (8) actuated to trigger the shutdown. 2. Overload shutdown device according to claim 1, characterized in that in per se known Way, the spring bias of the blocking z. B. adjustable by means of a threaded piece (9) is executed. 3. Overload shutdown device according to claim 1, characterized in that the contact position is adjustable, so that when giving way to the blocking, the path from the full load limit to the contact can be adjusted as desired, z. B. by changing the length of the contact pin (7). 4. Overload shutdown device according to claim 1, characterized in that several equal or one behind the other contacts are present, the z. B. a warning system, a parking facility for the engine or a disconnection device for the drive clutch. 5. Overload shutdown device according to claim 1, characterized in that the response speed is very low and only the drive clutch is released so that the engine stops is avoided. Pamphlets considered; German patents No. 733 037, 826 665, a threaded piece 9 and also the path 10 to 60 917 106; Making contact, e.g. by means of a length adjustability, Swiss patent specification No. 296 111. of the contact pin, to be changeable. The overload switch-off can all ^Contemplated older patents: Power machines are used which have a speed- German Patent No. 1 045 721. 1 sheet of drawings 909 768/133 3.