JPH0466772A - Fuel injection pump - Google Patents

Abstract

PURPOSE:To automate assembly of a fuel injection pump using a robot by fitting an L-shaped rack into a rack fitting hole in such a manner that the rack can be projected into and pulled back from the pump unit through hole of a pump main body, and enabling a pump unit to be inserted into the pump unit through hole from above, the rack fitting hole being provided in the pump main body. CONSTITUTION:This fuel injection pump device has an L-shaped rack 1 disposed in a rack fitting hole 23 in such a manner as freely sliding and the L-shaped rack 1 can be engaged with an engagement protrusion 5 at an engagement channel 1b in order to put a control sleeve 4 in a turning movement. A pump unit through hole A is opened through a pump main body C and a pump unit U is inserted into the through hole A from above. In this case, to enable the pump unit U to be inserted into the through hole A while the rack 1 is inserted therein, a recessed portion 1a is formed in the rack 1 and the rack 1 is put in a turning movement so that the recessed portion 1a projects into the through hole A. A cam tapped 16 which supports a cam drive wheel 11 engages a lock pin 24 in a stroke long hole provided in the cam tapped 16 so as to keep the pin from coming off.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a structure that allows a fuel injection pump to be automatically assembled by a robot or the like.

(b) Prior Art The structure of a fuel injection pump has been known in the art.

However, the conventional fuel injection pump is basically constructed by manual assembly on an assembly line, and a protruding abutment step for assembly is provided at an intermediate position above and below the pump unit insertion hole drilled in the pump body. The lower part of the plunger is inserted from the bottom of the contact step and fixed by the final screw to prevent removal, and the upper part of the plunger is also inserted from the top of the contact step. The uppermost part of the pulp case was designed to prevent these from falling out upwards.

However, with the method of assembling the fuel injection pump by inserting each half of the fuel injection pump parts from the top and bottom of the pump unit insertion hole opened in the pump body, it is impossible to automate the assembly using a robot.

As a prior art, a technique such as that disclosed in Japanese Unexamined Patent Publication No. 118550/1988 is known.

(c) Problems to be Solved by the Invention In order to automate assembly, instead of providing a contact step in the center, all openings are oriented in one direction so that parts can be inserted one after another in the same direction. is the easiest to automate.

However, it is absolutely necessary to have a contact step that receives thrust from the pump drive cam from below, and in order to configure this contact step, the present invention provides a pump unit that can be inserted from above into the pump body. A fixing pin is provided for locking.

Furthermore, a rack driven by the governor unit protrudes inside the pump unit insertion hole formed in the pump body, and because of this rack, it is difficult to insert the pump unit from above.

According to the present invention, a recess is provided in the rack to allow insertion of a pump unit.

(d) Means for Solving the Problems The problems to be solved by the present invention are as described above. Next, the means for solving the problems will be explained.

A cam tappet 16 is fitted into a hole provided in the pump body facing the pump drive cam, and a rack fitting hole 23 is provided along the right angle direction at a suitable position on the inner peripheral surface of the hole facing the pump drive cam. At 23, a rack having a cross-section shape is fitted so as to be retractable into the pump unit insertion hole of the pump body,
Insert a pump unit that integrates a plunger, a lower spring holder, an upper spring holder, and a control sleeve interposed between the plunger and the upper spring holder into the pump unit insertion hole, and insert the fixing pin into the outside of the pump body. It was inserted from.

Further, the fixing pin is inserted from the outside of the pump body into a fixing pin insertion hole opened between adjacent pump unit insertion holes.

Further, the L-shaped rack is provided with a recess through which the outer circumferential surface of the upper spring receiver can pass, and an engagement groove for the control sleeve.

(E) Embodiment The problems to be solved by the present invention and the means for solving them are as described above.Next, the structure of the embodiment shown in the attached drawings will be explained.

FIG. 1 is a side sectional view of the fuel injection pump device, FIG. 2 is a plan sectional view, and FIG. 3A is a rear sectional view.

The fuel injection pump device illustrated in FIGS. 1 to 3A is as follows:
It is for a three-cylinder engine, and is fixed to a part of the cylinder block, and the rotation of the crack shaft of the diesel engine is transmitted to the pump shaft 24.

The pump shaft 24 is bearinged inside the pump body C, and three pump drive cams 10 protruding from the outer periphery of the pump shaft 24 move the cam drive wheel 11 up and down.
12.

Further, a governor weight 26 is disposed at the end of the pump shaft 24, and the governor weight 26 is expanded by the centrifugal force of the rotation of the pump shaft 24, and the L in the rack insertion hole 23 is expanded via the governor link mechanism. The character-shaped rack 1 is slid.

The L-shaped rack 1 is arranged inside the rack insertion hole 23, and in order to rotate the control sleeve 4, the engagement protrusion 5 protruding from the control sleeve 4 has an engagement groove 1b.
The parts are engaged.

A pump unit insertion hole A is opened in the pump body C, and the pump unit insertion hole A allows the pump unit to be inserted only from above. It is necessary to receive the pushing up force at the upper spring receiver 3, and a fixing pin insertion hole 25 is provided into which the fixing pin 2 can be inserted from the outside of the pump body C.

A pre-heli-valve case 15 is provided projecting from the upper part of the pump body C.

FIG. 3, FIG. 4, FIG. 5, and FIG. 6 are drawings showing a method of assembling a fuel injection pump in order.

In FIG. 3, the L-shaped rack 1 is inserted in advance into the lath insertion hole 23 opened in the pump body C, and in this state, the pump unit shown on the left side of FIG. 4 is inserted into the insertion hole A. In order to allow insertion, the L-shaped rack 1 is rotated as shown in FIG. 3 with the recess 1a provided in the L-shaped rack 1 protruding into the insertion hole A. .

Further, a cam tappet 16 bearing the cam drive wheel 11 is fitted inside the pump unit insertion hole A, and a tappet locking pin is installed to prevent the cam tappet 16 from falling out from below the pump unit insertion hole A. 24 is inserted inside the stroke elongated hole provided in the cam tappet 16.

FIG. 3 shows a state in which the L-shaped rack 1, cam tappet 16, and tappet locking pin 24 are fitted, and the pump unit U shown in FIG. 4 is inserted into the pump unit insertion hole A in this state. be.

The pump unisol L-U includes a lower spring receiver 14 at the lower end of the plunger 12, an upper spring receiver 3 in the middle, a control sleeve 4 interposed between the upper spring receiver 3 and the plunger 12, and a lower spring receiver 14. The return spring 17 interposed between the upper spring receiver 3, the plunger barrel 13, the delivery valve seat 21 fitted from above the plunger barrel, the delivery valve 20, the urging spring 22, and these It is composed of a delivery valve case 15 and the like to be housed therein.

The plunger 12 is provided with a plunger lead 18 formed by an inclined notch, and the plunger barrel 13 is provided with a barrel hole 17.

The pump unit U composed of these parts is inserted from above into the pump unit insertion hole A into which the cam tappet 16 and the L-shaped rack 1 have been inserted, and then fixed from the side as shown in Fig. 5. Fix pin 2 in pin insertion hole 25
It locks by inserting it into the

Thereafter, the L-shaped rack 1 is rotated about 80 degrees, and the engaging groove 1b is fitted onto the outside of the locking protrusion 5 provided on the control sleeve 4 for engagement.

Figure 7, Figure 8, Figure 9, Figure 10, Figure 11, Figure 12
FIG. 6 is a diagram showing another automatic assembly sequence shown in FIG.

As shown in Fig. 7, there is an L inside the pump unit insertion hole A.
It is the same that the character-shaped rack 1 and the cam tappet 16 are inserted. A cam driving wheel 11 is pivotally supported on the cam tappet 16, and is locked by a tappet locking pin 24 so that vertical stroke movement is possible but rotation is impossible.

Into the pump unit insertion hole A is inserted a pump unit U°, which is an integrated structure of a lower spring receiver 14, a return spring 17, an upper spring receiver 3, a control sleeve 4, and a plunger 12, as shown in FIG.

The pump UNISO) U differs from the U of the previous embodiment in that the plunger barrel 13 and the delivery valve UNISOTO are separate.

Then, the fixing pin 2 is inserted through the fixing pin insertion hole 25 on the side surface while the upper part of the upper spring receiver 3 and the control sleeve 4 can be monitored.

After that, as shown in FIG. 11, the plunger barrel 13 is fitted into the pump unit insertion hole A, and then the pre-heli valve seat 21, the biasing spring 22, the delivery valve 20, and the delivery valve case 15 are fitted and screwed. That's what I do.

13 and 14 are a side view and a top view of the L-shaped rack 1, FIGS. 15 and 16 are a bottom view and a front view of the fixing pin 2,
FIG. 17 is a plan view of the fixing pin 2 inserted into the upper part of the upper spring receiver 3, and FIGS. 18, 19, and 20 are a plan view, side sectional view, and front view of the upper spring receiver 3. .

The L-shaped rack 1 is provided with a pin lc that connects the end to the governor link mechanism, and a recess 1a through which the cam tappet 16 and the upper spring receiver 3 can pass is provided in the middle. Further, an engagement groove 1b is provided which engages with the locking protrusion 5 after the cam tappet 16 and the upper spring receiver 3 have passed through.

The fixing pin 2 has a stepped portion 2c at its tip and fits between the left and right pump units U, so it does not start contacting the left and right upper spring receivers 3 at once, but one by one. A lower spring receiver 14 is provided for contact.

Further, as shown in FIG. 16, T-shaped contact portions 2a and 2b are provided, and the contact portions 2a and 2b contact the cutout contact portions 3b and 3b of the left and right upper spring receivers 3 from above. This prevents the upper spring receiver 3 from moving upward.

3a is a protruding wall portion.

(F) Effects of the Invention Since the present invention is constructed as described above, it has the following effects.

With the configuration as claimed in claim (1), the pump unit insertion hole A that opens in the pump body C does not need to provide an abutting step part in the middle, so all the parts constituting the pump unit 7) U are connected upwardly. It became possible to insert it from there.

In particular, the part of the upper spring receiver 3 that receives the force from the pump drive cam 10 is configured to be received by the fixing pin 2 that is inserted into the fixing pin insertion hole 25 from the outside, so that all assembly of the fuel injection pump can be done from above. This can now be done by inserting parts, making unmanned assembly work possible with robots.

Since the structure is configured as in claim (2), by inserting one fixing pin 2 into the fixing pin insertion hole 25, the upper splash receivers 3 of the two fuel injection pumps are prevented from moving upward. A joint can be formed, and the pump unit insertion hole A
Since it can be constructed with only half the number of fixing pin insertion holes 25 and fixing pins 2, assembly can be simplified.

Since the configuration is as set forth in claim (3), when the cam tappet 16 and the upper spring receiver 3 pass, the L-shaped rack 1
When tilted, the recess 1a faces the pump unit insertion hole A, and since the recess 1a has a diameter larger than the diameter of the pump unit insertion hole A, the cam tappet 16 and the upper splash receiver 3 are It passes easily.

By rotating the L-shaped rack 1 after the upper spring receiver 3 has passed, the locking protrusion 5 can be locked in the engagement groove 1b.

[Brief explanation of the drawing]

Figure 1 is a side sectional view of the fuel injection pump device, Figure 2 is a plan sectional view, Figure 3A is a rear sectional view, and Figures 3 and 4.
1 shows how to assemble the fuel injection pump, and 7, 8, 9, 10, 11, and 12 show how to assemble the fuel injection pump. Drawings showing the order of assembly, FIGS. 13 and 14 are a side view and a plan view of the L-shaped rack 1,
15 and 16 are bottom and front views of the fixing pin 2, FIG. 17 is a plan view of the fixing pin 2 inserted into the upper part of the upper spring receiver 3, and FIGS. 18, 19, and 20. The figures are a plan view, a side sectional view, and a front view of the upper spring receiver 3. 10...Pump drive cam 11...Cam drive wheel 12...Plunger Applicant Yanmar Diesel Co., Ltd. Agent Patent attorney Toshihiro Yano Curriculum-shaped rack/recess/engaging groove fixing pin upper splash receiver control sleeve Locking protrusion Fig. Fig. Fig. 13 b Fig. b Fig. 20 b Fig. 19

Claims (3)

[Claims] (1). A cam tappet is fitted into a hole provided in the pump body facing the pump drive cam, a rack fitting hole along the right angle direction is provided at an appropriate position on the inner peripheral surface of the hole facing the pump drive cam, and a cross section is formed in the rack fitting hole. An L-shaped rack is removably fitted into the pump unit insertion hole of the pump body, and the plunger, the lower spring holder, the upper spring holder, and the intervening parts between the plunger and the upper spring holder are inserted into the pump unit insertion hole. A fuel injection pump characterized in that a pump unit integrated with a control sleeve is inserted, and a fixing pin is inserted from the outside of the pump body. (2). A fuel injection pump characterized in that the fixing pin according to claim 1 is inserted into a fixing pin insertion hole opened between adjacent pump unit insertion holes from the outside of the pump body. (3). A fuel injection pump characterized in that the L-shaped rack according to claim 1 is provided with a recess through which the outer peripheral surface of the upper spring receiver can pass and an engagement groove for the control sleeve.