US3350517A

US3350517A - Ignition distributor with improved means for adjusting the breaker points

Info

Publication number: US3350517A
Application number: US517714A
Authority: US
Inventors: Raymond A Soeters
Original assignee: Holley Carburetor Co
Current assignee: Holley Performance Products Inc
Priority date: 1965-12-30
Filing date: 1965-12-30
Publication date: 1967-10-31
Anticipated expiration: 1984-10-31
Also published as: DE1526779A1

Description

Oct. 31, 1967 R. A. SOETERS 3,350,517 IGNITION DISTRIBUTOR WITH IMPROVED MEANS FOR ADJUSTING THE BREAKER POINTS Filed Dec. 30, r 1965 3 Sheets-Sheet 1 I i IHIH I W T l /44 j! H I 5,).L1/2 5e 5 I II .92 62 44 I 4o 36 b -1 L@ 30 k Y 30 INVENTOER, 2a 34 F RAY/V040 A 5057' R5 32 36 BY m 5,4. #762 W ATTOR/VfYS Get. 31, I967 R. A. SOETERS 3,350,517 IGNITION DISTRIBUTOR WITH IMPROVED MEANS FOR ADJUSTING THE BREAKER POINTS Filed Dec. 30, 1965 5 Sheets-Sheet 2 A30 Oct 31, W67

, R. A. SOETERS 3,350,517 IGNITION DISTRIBUTOR WITH IMPROVED MEANS FOR ADJUSTING THE BREAKER POINTS Filed Dec. 30, 1965 5 Sheets-Sheet 5 FAY/40W ,4. $057595 INVENTOR.

United States Patent 3,350,517 IGNITION DISTRIBUTGR WITH IMPROVED MEANS FOR ADJUSTING THE BREAKER POHVTS Raymond A. Soeters, Royal Oak, Mich assignor to Holley Carburetor Company, Warren, Mich., a corporation of Michigan Filed Dec. 30, 1965, Ser. No. 517,714 13 Claims. (Cl. 200-31) ABSTRACT OF THE DISCLOSURE An ignition distributor having means for adjusting the breaker points externally while the engine is running, wherein the adjustment means is not an integral part of the breaker point assembly.

This invention relates generally to automotive type ignition distributors, and more particularly to an improved ignition distributor having as one of its principal features means for adjustment of the breaker contact gap and dwell from the outside of the distributor while the engine is running.

Externally adjustable breaker art, an example thereof being disclosed in Julian et al. 2,816,968. However, the adjustment mechanism taught by Julian is an integral part of the breaker point assembly. This means that the consumer necessarily pays a cost penalty whenever he replaces points, since the cost of the contact set includes the cost of adjusting mechanism.

Accordingly, a main object of this invention is to pro vide an ignition distributor constructed in a manner so that the contact set may be adjusted from the outside of the distributor while the engine is running, thus simplifying and shortening the time required by the mechanic to service the distributor.

Another object of the invention is to provide such a distributor wherein the means for adjusting the breaker points is not an integral part of the breaker point assembly, but associated with the breaker or advance plate assembly on which the breaker points are mounted and which does not normally require replacement during the life of the distributor.

Another object of the invention is to provide such an ignition distributor wherein the adjustment means is between the usual movable breaker plate and an adjusting bracket on which the breaker point assembly is mounted.

Still another object of the invention is to provide a distributor wherein the adjustment bracket, to which the breaker point assembly is directly connected, is pivotally secured to the movable breaker or advance plate.

Still another object of the invention is to provide a dis tributor wherein the movable breaker plate is formed in a manner so that a universal design may be employed for both clockwise and counterclockwise vacuum spark advance distributors.

A still further object of the invention is to provide a distributor wherein a structural feature of the movable breaker plate assembly serves the dual function of securing the adjusting bracket thereto, with clearance to enable the operation thereof with minimum friction, and properly locating the breaker points on the movable breaker plate and adjusting bracket assembly,

A still further object of the invention is to provide such a distributor wherein the breaker point assembly is held against the movable breaker plate under a predetermined spring force so as to eliminate vibration but to allow adjustment thereof, the structure being such that the predetermined spring force cannot be exceeded.

Another object of the invention is to provide a distributor wherein spring means holding the movable breaker points are known in the plate on the fixed distributor plate can be easily applied and removed and cannot be moved from its proper position, as by vibration during operation of the distributor.

Still another object of the invention is to provide such a distributor wherein the opening in the wall of the distributor housing that provides access to the distributor point adjusting mechanism is sealed against dust by a unique resilient seal and wherein guide means for the adjusting tool is provided so as to prevent the tool from being inadvertently inserted into moving parts of the distributor when adjustment is made while the engine is running.

A further object of the invention is to provide such a distributor wherein said adjusting means is such as to not interfere or prevent the use of a dust cover between the distributor base and the distributor cap; that is, the use of a dust cover, which is highly desirable, does not in any way interfere with adjustment of the distributor points from the outside of a completely assembled distributor.

These and other objects and advantages of the invention will become more apparent upon reference to the following specification and the accompanying drawings wherein:

FIGURE 1 is a top plan view of an ignition distributor embodying the invention, with the distributor cap and dust cover removed, the view being taken on the plane of line 1-1 of FIGURE 2.

FIGURE 2 is a cross-sectional view on the plane of line 22 of FIGURE 1, looking in the direction of the arrows and with the distributor cap and dust seal in place.

FIGURE 3 is a cross-sectional view taken on the plane of line 3-3 of FIGURE 1 and looking in the direction of the arrows.

FIGURE 4 is a fragmentary side elevational view taken substantially on the plane of line 44 of FIGURE 1 and looking in the direction of the arrows.

FIGURE 5 is a double size top plan view of the distributor plate and breaker plate assembly removed from the distributor housing.

FIGURE 6 is a side elevational view of the assembly shown by FIGURE 5, with a portion thereof in crosssection.

FIGURE 7 is a bottom plan view of the breaker plate and adjusting bracket assembly forming a part of the assembly shown by FIGURE 5.

FIGURE 8 is a side elevational view of the assembly shown by FIGURE 7.

FIGURE 9 is a top plan view of the assembly shown by FIGURE 7.

FIGURE 10 is an enlarged fragmentary cross-sectional view taken on the plane of line 1010 of FIGURE 7 and looking in the direction of the arrows.

FIGURE 11 is an actual size bottom plan view of the assembly shown by FIGURE 5.

Referring now to the drawings in greater detail, FIG- URES 1 and 2 illustrate a distributor 10 comprising a cylindrical housing 12 having an open end 14 on which a generally cylindrical distributor cap 16, the structural details and the function of which is well known in the art so that it need not be described, is mounted and retained by means such as spring clips 18. A distributor shaft 20 is mounted axially within the housing 12, the shaft being driven by the engine (not shown) as is well known in the art.

The particular distributor 10 shown is essentially identical to that shown in Bettoni et al. 3,207,864 insofar as the housing 12, the shaft 20, the distributor cam 22, and the centrifugal advance mechanism 24 are concerned. Since these general features form no part of the present invention, they will not be described in detail. By referring to Bettoni et al. 3,207,864, it will be apparent that the distributor cam member 26 is mounted on the shaft 20 in a manner so as to permit relative rotation thereof with respect to the shaft. The cam member 26 is formed with integral pins 28 received in slots 30 formed in the centrifugal weights 32, each of which is pivotally mounted on the plate 34 which is fixed to the shaft 20 so as to rotate therewith. Thus, rotation of the distributor shaft 20 will cause the weights 32 to move outwardly on their pivots, and engagement of the pins, over which bushings 36 may be fitted, with the slots 30 i nthe weights 32 will cause rotation of the cam member 26 with respect to the shaft 20 so as to advance the spark in accordance with engine speed.

As is well known in the art, it is also desirable to advance and/ or to retard the spark in response to engine manifold vacuum conditions. For this purpose, the distributor is provided with a vacuum diaphragm assembly 38 which is essentially identical to that shown in Bettoni et al. 3,207,864 and the operation of which will be described below.

In view of the above discussion, it will be apparent that the novelty of the distributor 10 lies in the structure provided within the distributor housing to affect advance and retard of the spark in response to engine manifold vacuum, as sensed by the vacuum diaphragm assembly.

This structure (see FIGURES 5, 6 and 11) comprises a fixed distributor plate 46 that is mounted on the annular shoulder 42 in the housing, in a position perpendicular to the axis of the distributor shaft 20. The distributor plate 46 is formed with a central opening 44 of sufiicient diameter so that the distributor cam 22, can pass therethrough, and the plate 41) is secured to the base 12 by any suitable means such as the two screws 46 received in the slots 48. The plate may be of any desired configuration to provide access to the other parts of the assembly, and it is provided wit-h a pivot pin bushing 50 and a slot 52 in the outer periphery thereof, the purposes of which will be described.

Included in the vacuum advance mechanism is the breaker plate and adjusting bracket assembly 54 best shown in FIGURES 7-l0. The breaker plate 56, which may be of any desired specific shape, includes a central opening 58, which is also of sufficient diameter to allow the distributor cam 22 to pass theret-hrough, and three substantially equally spaced holes 60 into which spacer buttons 62 may be inserted from either side thereof, the buttons 62 serving the purpose of mounting the breaker plate 56 on the fixed distributor plate 46 in parallel relation thereto and being made of a low-friction, wear-resistant material so as to allow movement of the breaker plate on the fixed distributor plate. The breaker plate 56 is also formed at one side thereof with an upturned tab 64 having an opening therein to receive the adjusting screw 66.

Spaced openings 68 are formed in the plate 56 to receive -a pin 70 to which the link 72 connected to the vacuum diaphragm 74 may be secured for the purpose of rotating the plate 56. By providing two openings 68, the pin 70 may be inserted in either opening, thereby adapting the plate to either a clockwise or counterclockwise spark spark advance mechanism.

The plate 56 is also formed with an extruded or punched opening 72 providing a ring 74 extending from one side of the plate and a corresponding circular depression 76 on the opposite side of the plate. Further, the plate 56 is formed with

spaced slots

78 and 80, a pivot pin 82 (see FIGURE 6) having an annular groove 84 near the free end thereof and with a threaded opening 86 having a pair of aligned

punched projections

88 and 90, one on each side of the openings.

The adjusting bracket 92 comprises a generally half circular

plate having posts

94 and 96 secured at opposite ends thereof, the bracket being assembled so that the

posts

94 and 96 extend through the

openings

78 and 80, respectively, in the breaker plate. The bracket is also formed with an opening into which the ring 74 formed on the breaker plate 56 is fitted with sufficient clearance to permit pivoting of the adjustment bracket 92. thereon. The bracket 92 is mounted and retained on the breaker plate 56 by means of the eyelet 98 which, as best seen in FIG- URE 10, is clamped on the opposite side of the ring 74 and which has a raised outer periphery 100 so as to overlie but not clamp the adjustment bracket.

The adjustment bracket 92 is also formed with an upturned tab 102 having a threaded opening 104 therein to receive the threaded adjustment screw 66. It will thus be apparent that turning the screw 66 in one direction or the other will cause the adjustment bracket 92 to pivot in a corresponding direction about the axis of the eyelet 98, causing the

posts

94 and 96 to move within the

slots

78 and 80, respectively, in the breaker plate 56. The helical spring 106 between the

tabs

64 and 102 maintain tension on the threads and the friction clip 108 is pressed on the threads of the screw 66 to provide a further friction or binding load that prevents the screw from turning due to vibration.

The breaker point set or assembly 110 may be of any standard design, it being noted that the bracket 112 therefor is provided with spaced openings 114 and 116' at the opposite ends thereof, the round opening 114 fitting the post 94 rather loosely and the other opening 116 receiving post 96 being somewhat elongated to accommodate manufacturing tolerances in the spacing of the

posts

94 and 96, but dimensioned to fit the post 96 snugly at the flat sides thereof so that any movement of the adjusting bracket 92 is transmit-ted to the breaker points bracket 112. It should be noted that it is not intended that the breaker point bracket 112 be movable With respect to the adjusting bracket 92; rather, the breaker point bracket 112, being fitted on the posts 94 and '96 moves with the adjustment bracket 92 when adjustment screw 66 is turned. The only other feature of the contact set 110 important to the invention is that the pivot post 118 for the movable contact arm extends below the contact bracket 112, the extension 120 fitting into the eyelet 98 to properly locate the breaker point set 110 on the breaker plate 56.

It will thus be apparent that the fixed distributor plate 40, the movable breaker plate and the adjusting bracket assembly 54 and the breaker point set 110 are assembled to provide the removable assembly 122 shown in FIG- URES 5, 6 and 11. Since the breaker point set 110 must be free to move on the surface of the breaker plate 56, rigid means for holding the same on the plate cannot be employed. Accordingly, the means for holding the breaker points down are the helical springs 124 surrounding the posts, 94 and 96, the latter each being internally threaded to receive a screw 126. The springs 124 have a free length such that when the screws 126 are tightened down on the posts, the springs are compressed a predetermined amount resulting in a proper spring holddown force. In other words, the

posts

94 and 96 are of such a height that turning the screws 126 down all the way will not cause the spring coils to bottom on one another. This design prevents a mechanic from excessively compressing the springs so as to prevent the movement of the breaker point set during adjustment thereof.

Access to the adjusting screw 66, the head of which is formed to receive an Allen wrench, is through the opening 128 formed in the side wall of the housing 12. This opening 128 is closed against the entry of dust and other foreign matter by the rubber or other resilient seal 130 which is held down by the cover 132 retained by screws 134. The portion of the seal aligned with the access hole 128 is formed with a slit 136 and the cover 132 is provided with aligned

openings

138 and 140 having a restricted height but a less restricted width. With this construction, the Allen wrench can be inserted through the aligned

openings

138 and 140 in the cover 132, forced through the slit 136 in the seal 130 and inserted into the head of the adjusting screw 66. A greater width of the aligned

openings

138 and 140 permits lateral freedom of movement of the Allen wrench to find the head of the vents the Allen wrench from downwardly, such as through the cut away portion 142 of the fixed distributor plate 40 and into the path of the rotating centrifugal advance ,assembly 24 when adjustment is made while the engine is running.

Thre condenser bracket 144 is formed with three openings, the center opening 146 receiving the holddown screw 148 and other openings receiving the spaced

projections

88 and 90 formed on the breaker plate, as by a punch operation, to properly position the condenser -152.

FIGURE 1 illustrates that the distributor cam 22 rotates in a counterclockwise direction and the plate 56 is rotated clockwise about its pivot 82 to affect vacuum spark advance. As previously stated, if an opposite spark advancing distributor is desired, the breaker plate 56 is formed with the pin 70 in the other hole 68, the assembly 122 mounted in the housing 12 in a 180 rotated position and the vacuum diaphragm assembly 33 is secured to the housing 12 upside down from the position shown in FIG- URE 1 so that the link 72 connected to the diaphragm 74 extends in the direction shown in dotted lines. This eliminates providing two sets of machined housings 12 and diaphragm assemblies 38, except possibly for forming the access holes 128 and the lead wire opening 129 in the distributor housing 12 on the opposite side thereof.

It should be noted that the adjustment screw 66 is readily accessible without the necessity of holding prior art spring-loaded access doors open to insert the adjusting tool and without in any way interfering with the highly desirable dust cover 154 between the distributor cap 16 and the housing 12.

The distributor plate 40 and plate 56 are resiliently retained in parallel relation on the slider blocks or buttons 62 by means of the spider type spring 156 which is applied by inserting the head of the pin 82 through the larger portion 158 of the opening in the spring 156 and sliding the spring laterally so that the narrower portion 160 of the opening engages the annular groove 84 in the pin 82. At the same time, a-downwardly turned end 162 of the leg 164 of the spring will drop into the slot 52 formed in the outer periphery of the fixed distributor plate 40.

OPERATION The operation of the distributor 10 shown is, as previously stated, similar to the operation of the distributor shown by Bettoni et al. The housing 12 is mounted on an engine (not shown) in a manner so that the shaft is driven by the engine. Springs associated with the weights 32 and the spring 166 in the diaphragm assembly 38 determine the initial positions of cam 22 with respect to the shaft 20 and the breaker plate with respect to the cam, respectively. When the engine is running and the shaft 20 is accelerated, the centrifugal force acting on the weights causes them to move outwardly against the force of their retaining rings, thereby rotating the cam 22 relative to the shaft 20. This advances and retards the spark, as is well known, in accordance with engine speed.

It is also desirable to advance or retard the spark in response to engine vacuum. Increased engine vacuum is communicated to the chamber 168 through the conduit 170, and the diaphragm 74 is moved against the force of its return spring 166. The link 72, being pivotally connected to the advance plate 56, causes the plate to move in a clockwise direction about its pivot 82. On the other hand, when the vacuum decreases, the diaphragm return spring 166 causes the advance plate to move in a counterclockwise direction. This rotation of the plate 56 changes the relationship between the cam 22 and the cam follower 172 on the movable contact arm 174, thereby changing the operation of the points.

When the point gap and dwell time need to be adjusted, or if the points are replaced so that such and adjustment must be made, and this is preferably done while the engine is running, the mechanic can simply insert the proper being inadvertently angled the breaker or advance screw 66, but the restricted height of these openings pre-l size Allen wrench through the guide holes 138 and in the cover 132, through the slit 136 in the seal 130 and then into the head of the adjusting screw 66 and turn the screw in the desired direction. As already stated, there is no spring loaded door or other dust seal to hold open, and when the Allen wrench is removed, the slit in the seal automatically closes.

Replacing the point set 110 is operation, and, due to the relationship between the free length of the springs 124 and the height of the

posts

94 and 96, it is impossible for the mechanic to tighten the screws down to the extent that the springs exert excessive pressure.

The breaker plate obviously a very simple 56 is constructed in a manner so that the same plate can be used for clockwise and counterclockwise operation, the only diflference being the location of the pin 70 for the diaphragm stem 72. In changing from one type of distributor to the other, the plate is, of course, rotated This repositions the adjusting screw 66 180, and the only difference in machining the distributor base is in the location of the adjustment screw access opening 128. As already stated, the diaphragm assembly 38 is also of a universal design so changing to the opposite type distributors merely requires that the diaphragm assembly be turned upside down in securing the same to the housing 12, the slot 176 through the wall of the housing 12 to receive the diaphragm link 72 being of suflicient length to accommodate either position thereof. Since the fixed distributor plate 40 is also necessarily rotated 180 in providing the opposite type of distributor, the threaded holes to receive the screws 46, which are located 180 apart, can accommodate either position of the plate 40.

It is apparent from the above description of construction and operation that the contact adjustment mechanism is not removed from the distributor and that the setting thereof is not changed when the breaker contacts are replaced. To remove the contact set, it is only necessary to remove the screws 126 and springs 124 and lift the contact set bracket 112 oil the

posts

94 and 96, after disconnecting the condenser and primary lead wires 178 and 180. Installing the new contact set involves the opposite procedure, and the previous contact adjustment may very well -suflice.

The invention has been disclosed and described in such detail that anyone skilled in the art may practice the same. While but one embodiment has been shown, modifications thereof may be possible within the scope of the appended claims, and no limitations are intended as except therein recited.

What I claim as my invention is:

1. An internal combustion engine ignition distributor, comprising a housing, a shaft in said housing to be driven by the engine, a cam on said shaft, fixed support means in said housing, movable support means pivotally mounted on said fixed support means, adjustment means, means movably mounting said adjustment means on said movable support means, a set of breaker contacts including a mounting bracket positioned adjacent said cam so as to be intermittently opened thereby, said bracket being fixedly mounted to said adjustment and means movably mounting said bracket on said movable support means, and means for moving said adjustment means with respect to said movable support means so as to adjust the position of said mounting bracket with respect to said cam.

2. A distributor such as that recited in claim 1, wherein said housing is generally cylindrical and open at one end, said open end being closed by a distributor cap, and wherein a dust seal is positioned between said cap and said housing.

3. A distributor such as that recited in claim 1, wherein said fixed support means comprises a distributor plate secured in said housing in a position perpendicular to the axis of said shaft.

4. A distributor such as that recited in claim 1, wherein said movable support means comprises a breaker plate and the pivotal mounting of said breaker plate on said distributor plate comprises a bushing on one of said plates and a pin extending from the other of said plates, said pin being received in said bushing, one of said plates having spacer members secured thereto to maintain said plates in parallel relation, said plates being held in'such parallel relation by a tripod type spring member cooperating with the free end of said pin, one of said plates having a notch formed therein and one of the legs of said tripod spring having a portion receivable in said notch so as to prevent rotation of said spring about said pin.

5. A distributor such as that recited in claim 1, wherein said movable support means comprises a breaker plate and the pivotal mounting of breaker plate on said distributor plate comprises a bushing on one of said plates and a pin extending from the other of said plates, said pin being received in said bushing, one of said plates having spacer members secured thereto to maintain said plates in parallel relation, said plates being held in such parallel relation by a spring co-operating with the free end of said pin.

6. A distributor such as that recited in claim 1, wherein said movable support comprises a breaker plate and said movable adjustment means comprises a late pivotally mounted on said breaker plate on the fixed support side thereof.

7. A distributor such as that recited in claim 6, wherein said breaker contacts include means associated with the pivot of said pivoted breaker contact arm pivotally mounting the same on said breaker plate on the axis of the pivotable mounting between said adjustment means and said breaker plate.

8. A distributor such as that recited in claim 6, wherein said breaker plate is provided with spaced openings elongated in converging directions and said adjustment plate has secured thereto a pair of spaced posts, each of said posts extending through one of said elongated openings in said breaker plate, and wherein said breaker contacts are provided with spaced openings, said breaker contacts being positioned on said breaker plate in a manner so that each of said openings receive one of said posts, said posts being internally threaded, said distributor having a coil spring positioned on each of said posts and a screw threaded into each of said posts so as to compress said springs and resiliently hold said breaker contacts on said breaker plate.

9. A distributor such as that recited in claim 1, wherein said movable support means and said adjustment means comprise adjacent plates and said last named means comprises a tab extending from one of said plates, another tab extending in the same direction from the other of said plates, said tabs having aligned openings, the opening of one of said tabs being threaded, and a screw received into said openings so that turning of said screw in either direction will move said adjustment means with respect to said movable support.

10. A distributor such as that recited in claim 9, wherein the wall of said housing is provided with an access opening adjacent said screw for the purpose of permitting insertion of a tool to operate said screw.

11. A distributor such as that recited in claim 10, wherein said access opening is closed by a seal.

12. A distributor such as that recited in claim 11, wherein said seal is retained on said housing by means having guide means limiting the angle of insertion of said tool so as to enable blind application thereof to said screw and to prevent inadvertent insertion thereof into moving parts of said distributor when said adjustment is made while the engine is running.

13. A distributor such as that recited in claim 1, wherein said means for moving said adjustment means comprises threaded means cooperating with said movable support means and said adjustment means.

References Cited UNITED STATES PATENTS 2,797,269 6/1957 Buck et a1. 20 03l 2,820,858 1/1958 Tompkins 20031 3,242,274 3/1966 Sanden 20031 BERNARD A. GILHEANY, Primary Examiner. H. BROOME, Assistant Examiner.