JPS638819Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a load detector that electrically detects the load of a diesel engine.

When attempting to optimally control the fuel injection timing and the like of a diesel engine depending on the operating state of the engine, it is desirable to detect the load electrically and supply it to the load input terminal of the controller.

For this reason, conventionally, as shown in Figure 1,
A load detector 2 is attached to a fuel injection pump 1, and a pump lever 5 that responds to a load control lever 4 provided on a governor 3 of the pump 1 and an input lever 6 of the load detector 2 are interlocked via a turnbuckle 7. Accordingly, the load detector 2 outputs a voltage value corresponding to the load of the engine.

Here, the load detector 2 is as shown in FIGS. 2 and 3.
As shown in the figure, the base of the wiper 9 is welded and fixed to a support shaft 8 on which the input lever 6 is fixed by spot welding, and a resistance band is arranged in an arc shape with the support shaft 8 as the center. By holding the tip of the wiper 9 in sliding contact with the wiper 9, the voltage value between one end of the resistance band 11 and the wiper 9 is output as a load signal. It is needless to mention in detail that a constant voltage is applied between both ends of the resistance band 11.

Furthermore, in order to equalize the contact between the tip of the wiper 9 and the resistance band 11 and prevent uneven wear of the sliding part, conventionally the tip of the wiper 9 is machined into an arc shape as shown in FIG. At the same time, a plurality of slits 12 were formed including this arc portion.

However, variations may occur in the shape of the wiper tip due to errors during processing or external forces applied during assembly work. Furthermore, in the past, the base of the wiper 9 was fixed to the support shaft 8 to prevent the wiper 9 from coming off the resistance band 11 due to the mounting load due to spring back, so the contact pressure of each foot at the tip of the wiper could be reduced due to the above-mentioned variations. There was a drawback that variations occurred. Furthermore, even if the shape of the wiper tip is formed exactly the same, if the wiper 9 is fixed at an angle due to an assembly error, variations will occur in the surface pressure between the legs of the wiper tip, as described above. As a result, the legs and their contact portions, which are subjected to large surface pressure, wear out quickly, resulting in a disadvantage that the durability of the load detector is impaired.

Furthermore, if a flat wiper without a slit is installed to reduce the surface pressure at the wiper tip, the surface pressure will be uneven due to diagonal contact, so in this case as well, the surface pressure on the sliding part should be made uniform. This was extremely difficult.

This invention was made in view of the above, and
The objective is to provide an inexpensive and durable load detector that is easy to manufacture and uses a flat wiper with low surface pressure, while also making the surface pressure on the wiper tip uniform and preventing premature wear. shall be.

In order to achieve this objective, the wiper of the present invention is constructed of a flat plate with excellent conductivity and elasticity.
The base of the wiper and the support shaft are coupled so that the plate surface of the wiper is parallel to the axis of the support shaft and rotatable in the direction of the plate surface.

Therefore, even if there is an imbalance in the contact pressure between the tip of the wiper and the resistance band due to variations that occur during wiper molding or installation, the wiper will automatically move due to the reaction force due to the uneven contact surface pressure. Since the non-uniformity is eliminated by rotation, so-called uneven wear is prevented.

Embodiments of the present invention will be described in detail below with reference to FIGS. 5 and 6. In the drawings, parts that are the same as those in the prior art are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

FIG. 5 is a perspective view showing an example of the wiper used in the present invention. The wiper 9 is made of a metal plate with excellent conductivity and elasticity. The tip of the wiper 9 has an arcuate portion 9a that slides into contact with the resistance band. At the same time, a mounting hole 9b to the support shaft 8 is formed at the center of the base end of the wiper 9.

Further, the wiper 9 configured as described above has a sixth
As shown in the figure, a mounting surface 8a is formed by cutting off a part of the outer peripheral surface of the support shaft 8 parallel to the axis of the support shaft 8.
is attached with screws 10.

Here, the head 10a of the screw 10 is formed larger than the diameter of the attachment hole 9b formed in the wiper 9, and the outer diameter of the threaded portion 10b of the screw 10 is formed smaller than the attachment hole 9b. And head 10
A and the threaded portion 10b are provided with a neck portion 10c that is slightly longer than the thickness of the wiper 9 and has a slightly smaller diameter than the inner diameter of the mounting hole 9b, so that the base of the wiper 9 can be attached to the support shaft 8. The wiper 9 is rotatably mounted only in the direction of the plate surface of the wiper 9, which is parallel to the axis.

Therefore, there may be a partial error in the curvature of the arcuate portion 9a at the wiper tip, or the wiper 9 may be attached to the spindle 8 at an angle, or an error may occur in the position of the mounting hole 9b, causing the tip of the wiper 9 to be distorted. Even if uneven surface pressure occurs in the sliding area between the resistance band and the resistance band, the wiper 9 automatically rotates around the neck 10c of the screw 10 due to the reaction force due to the uneven surface pressure. Eliminate the non-uniformity.

For this reason, early wear of the sliding portion due to non-uniform surface pressure, which is conventional, is avoided, and the durability of the load detector is improved.

In addition, vibrations from the engine, injection pump, etc. are transmitted to the support shaft and the case that holds the resistance band, and although the vibration characteristics of the support shaft and the case are different, the wiper can be freely rotated around the support shaft. Since it is installed, vibrations are absorbed and damped at the joint between the spindle and the wiper. For this reason, relative vibration occurring between the wiper and the resistance band is suppressed, and abnormal wear caused by vibration can also be suppressed.

As explained above, according to the present invention, even if the wiper is constructed of a flat plate that is easy to process and can reduce the surface pressure, the contact between the wiper and the resistance band can be made uniform and the surface pressure will not be affected by processing errors, assembly errors, etc. Since uniformity can be avoided, early wear of the sliding portion between the wiper and the resistance band can be prevented and the durability of the load detector can be improved. Further, unlike the conventional method, it is not necessary to provide a slit at the tip of the wiper, and the assembly of the wiper does not require great precision, so the manufacturing cost of this type of load detector can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an example of mounting a load detector, Fig. 2 is a circuit diagram of the load detector, Fig. 3 is a sectional view of a conventional example, Fig. 4 is a perspective view of a conventional wiper, and Fig. 5 The figure is a perspective view of an example of a wiper used in the present invention, and FIG. 6 is a sectional view of essential parts showing an embodiment of the present invention. 1...Fuel injection pump, 2...Load detector, 3
...Governor, 4...Load control lever, 8
...Spindle, 9...wiper, 10...screw.

Claims (1)

[Scope of utility model registration request] A support shaft that rotates as the load control lever of the fuel injection pump rotates, a resistance band arranged on the inner surface of a cylindrical surface centered on the support shaft, and a base with the tip pressed against the resistance band. A load detector for a diesel engine, comprising: a wiper attached to the support shaft, the tip of the wiper sliding along the surface of the resistance band as the load control lever swings; is composed of a flat plate with excellent conductivity and elasticity, the plate surface of the wiper is held parallel to the axis of the spindle, and its base is connected to the spindle so as to be rotatable in the direction of the wiper plate surface. A diesel engine load detector characterized by: