US2317402A

US2317402A - Electric brake controller

Info

Publication number: US2317402A
Application number: US357589A
Authority: US
Inventors: William F Penrose
Original assignee: EMPIRE ELECTRIC BRAKE CORP
Current assignee: EMPIRE ELECTRIC BRAKE Corp
Priority date: 1940-09-20
Filing date: 1940-09-20
Publication date: 1943-04-27
Anticipated expiration: 1960-04-27

Description

April 27, 1943. w. F. PENRosE 2,317,402

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ELECTRI C BRAKE CONTROLLER Filed sept. 2o, 1940 s Sheets-sheet 2 INVENTOR //z//zaffz //Defzfae BY Y GMM@ 'Dm IMM @www ATTORNEYS.

April 27, 1943. w. F. PENRosE 2,317,402

ELECTRIC BRAKE CONTROLLER Filed Spt.A 20, 1940 3 Sheets-Sheet I5 BY RMC* IMM?? 2a-MJL ATTORNEYS Patented Apr. 27, 1943 ELECTRIC BRAKE CONTROLLER William F. Penrose, Irvington, N. J., assignor to Empire Electric Brake Corporation, a corporation of Delaware Application September 20, 1940, Serial No. 357,589

1 Cla-im.

This invention relates to controllers for electric brakes, and has for its principal object to provide an electric brake controller of erlicient and compact design.

Electric brake controllers of the type heretofore most commonly constructed are exemplified by the controller shown in United States Patent No. 1,952,679 toLeveen. Such controllers are characterized by a considerable number of leaf spring contacting members which are successively brought into contact with a contact lever as the lever is depressed, thereby successively shortcircuiting a series of resistance elements. Such controllers are open to the objection that they are relatively complicated to manufacture and are necessarily bulky. The relatively bulky nature of such controllers is necessitated by the large number of leaf spring contacts, the shortest of which must be suiciently long to possess adequate resilience and resistance to bending and breakage in severe service. 'I'he large number of spring contacts in such controllers, moreover, constitutes a source of weakness which impairs the reliability of the controller.

In accordance with the present invention, I have provided a controller which may be designed compactly and which is comparatively simple to manufacture and reliable in operation under even the most severe conditions. Briefly, the controller of the invention comprises a base plate on which a control winding, advantageously a single layer resistance coil, is mounted. A controller lever is pivotally mounted on the base plate in operative position relatively to the control winding. The controller lever operates a contact member, which member is in contact with the control winding and is movable by operation of the lever from an olf-position into contact with and along the active portion of the control winding. Spring means acting on the controller lever are provided urging the lever in a direction to bring the contact member operated thereby to the off-position, but such spring means, of course, permits the Contact member to be moved from the olf-position into contact with and along the active portion of the control winding upon application of a force in the proper direction to the lever.

The control winding advantageously is wound on a form which is held by suitable brackets in spaced relation with the base plate of the controller. The contact member then extends from the controller lever into the space between the control winding and the base plate and makes contact with the underside of the control winding. The arrangement of the parts provides for economical and compact design of the controller.

A stop-light switch may be mounted on the base plate of the controller in such position that the controller lever, when in an oil-position, engages and opens the switch, but such that initial movement of the controller lever from the off-position disengages the lever from the switch and causes the switch to close, thus causing the stop-light to be lighted.

A feature of the invention is the provision of adjustable means for limiting travel of the controller lever and thereby limiting the maximum amount of current that may be supplied to the electrically operated brakes. Such a provision is of pa-rticular value in the case of controllers mounted on tractor vehicles hauling trailers equipped with electric brakes, for it provides a simple and effective means for adjusting the controller on the tractor to operate most effectively with the particular design and number of brakes with which the trailer is equipped. Such a provision is also of value to set the controller to conform with .the particular road conditions being encountered at any time by the vehicle on which it is mounted.

The adjustable means for limiting travel of the controller comprise a stop, advantageously mounted on the base plate of the controller and so positioned as to engage the controller lever and limit the travel thereof. Adjustable means are provided for adjusting the position of the stop relatively to the controller lever to adjust the permitted travel of the lever to a -desired extent.

The invention will be better understood from the following description of specific embodiments of the invention, considered in connection with the accompanying drawings, in which- Fig. 1 is a view, partially in cross-section, of one form of controller constructed in accordance with the invention;

Fig. 2 is a vertical section taken substantially along the line 2-2 of Fig. l;

Fig. 3 is a top plan View of the controller shown in Figs. 1 and 2;

Fig. 4 is a vertical section taken substantially along the line 4 4 of Fig. 3, showing the adjustable stop assembly;

Fig. 5 is a bottom plan oi the controller shown in Figs. 1 to 4;

Fig. 6 is an elevation of the controller shown in Figs. 1 to 5:

Fig. 7 is a plan of a modified form of controller with cover removed; and

Fig. 8 is a vertical longitudinal section through the controller shown in Fig. 1.

The controller shown in Figs. 1 to G comprises a base plate l0 to which is secured a bracket Il carrying a clamp l2 for fastening the controller to a truck steering column or other suitable support I3.

Mounted on the base plate l0 is a winding form I 4 on which is wound a suitable control winding. The control winding advantageously comprises a single layer coil of resistance wire helically wound on the form I4. The resistance winding is connected at one end to a copper or other suitable metallic band I to which electrical connection may be made. At the other end of the form I4 the control Winding terminates just short of `and out of contact with a metallic or other suitable wear-resistant band I6 which provides an offposition. The winding form and control winding thereon is supported by brackets II riveted or otherwise suitably secured to the base plate l0. The brackets I'I, as shown in the drawings, 4are provided with end plates I8 which are held in rm engagement with the Winding form I4 by a bolt I9. firmly mounted on and in spaced relation with the base plate I l.

A controller lever 2B is pivotally mounted on the base plate at a suitable position relatively to the control winding. A pin 2| extending through an apertured boss 22 on the lever 29 provides the pivotal mounting for thelever. A brushing 23 may be provided to reduce friction between the lever 'and the pivot pin 2|. The lever 23 includes a relatively long arm 24 extending outwardly beyond the base plate I0, and a relatively short arm 25 extending inwardly toward the control winding on the form I4.

Mounted on the lever arm 25 is a contact member 26. This contact member advantageously is formed of springy metal, and it extends into contact with the control winding on the form I4 in the space between the winding form and the base plate Il). Rivets 2 serve to fasten the contact arm 26 to the short arm 25 of the controller lever, and insulating material 28 insul'ates the contact member therefrom. A lug 29 in contact with the contact member 25 is provided for making electrical connection to the contact member.

A torsion spring 33 fastened at one end to the short arm 25 of the controller lever and at the other end to a non-rotatable cap 3! is provided to urge the lever 20 and the contact member 2S carried thereby to the off-position. A fixed stop 32 limits the extent to which the spring 3B can move the lever in this direction.

From the foregoing it will be Aapparent, that movement of the long arm 24 of the controller lever serves to move the contact member 25 along and in contact with the control winding on the form I4. The farther the lever 24 is moved (downwardly in the form of apparatus shown in Fig. 1) against the pressure of the spring 3l), the farther the contact member 2S is moved along the control resistance winding away from the olfposition thereof land toward the full on-position, in the manner of a simple rheostat. Upon releasing the force'thus applied to the lever, the spring returns this member and the contact member 26 to the olf-position.

A stop-light switch 25 may be mounted on the base plate I Il in suitable position relatively to the controller lever 22. The switch 35 advantageously is a normally closed microswitch which is opened when pressure is applied to a plunger 36. The mounting of the stop-light switch 35 is such that when the controller lever 20 is brought to the olfpositicn by the action of the spring 3l) and abuts against the stop 32, the short arm 25 of the lever presses on the plunger 38 of the switch and causes the switch to open. Initial movement of the controller lever from the off-position releases the pressure exerted by the short arm 25 thereof on the switch plunger 3S and enables the switch to close, thus lighting the vehicle stop-light. Binding posts 3l on the stop-light switch are pro- In this manner the winding form I4 isA vided for making the necessary connections to the vehicle battery and the stop-light.

The controller mechanism is suitably enclosed by a cover 38 fastened by lugs 39 to the b ase plate It. An aperture 40 formed in the cover 38 is provided to accommodate the long arm 24 of the controller lever.

The controller shown in Figs. 1 to 6 is provided with an adjustable stop member 4I for limiting the travel of the controller lever 20 and the contact member 26 carried thereby. The adjustable stop 4I is secured to (advantageously it is formed integrally with) a hollow shaft 42, which shaft is mounted pivotally on a pin 43 anxed to the base plate Iii. The shaft 42 (Figs. 3 and 4) extends upwardly to a point outside the cover 38 and carries at its upper end a stop-adjustment lever 44. The lever i4 is formed with a D-shaped, square or other suitable opening for non-rotatable mounting on the shaft 42, and it is held in place by a cap nut or other suitable means 46. Thus by manipulating the lever 44, the shaft 42 may be turned about its pivotal mounting, and the position of the stop 4I thereby is adjusted relatively to the short arm 25 of the controller lever.

The stop-adjustment lever 44 advantageously is provided with a handle 47, and within the handle portion of the lever is mounted a ball 43 urged downwardly by a compression spring 49. In turning the lever 44, the ball 48 rides over a plate 5I) fastened tothe cover 38 of the controller. A series of depressions 5I are formed in the plate 52 in the line of travel of the ball 48, and when the lever is moved into opposition with any of these depressions, the ball 48 is pressed therein by the spring 49. The springpressed ball 48 and the depressions 5I thus provide a plurality of non-rigid detents, which serve to hold the lever 44 and the stop 4I connected thereto non-rigidly in any of the positions predetermined by the location of the depressions 5I. The plate in which the depressions 5I are formed advantageously is fastened to the controller cover 33 by bolts 52. The cover may be slotted along the arcuate line of travel of the ball 48 at the point where the bolts 52 pass therethrough and where the depressions 5I occur so as to permit of limited adjustment of the position of the plate 5o.

The non-rigid detents provided by the ball 48 and depressions 5I hold the lever 44 and the stop 4I connected thereto in position with suicient firmness so that the stop 4! limits the travel of the controller in the direction away from the off-position when a normal operating force is applied to the long arm of the controller lever. When, however, a greater than normal force is applied to this lever, as when an emergency stop is being made, the stop 4I may be forced out of the way to permit the lever 2l] and the contact member 25 carried thereby to be moved to the full-on-position of the controller winding and thus energize the electric brakes to the maximum extent possible. If desired, a xed stop53 may be provided to prevent the adjustable stop 4I from being moved beyond the point corresponding to a full-on-position of the controller.

The adjustable stop mechanism described above is of considerable value for use on controllers mounted on tractors which in the regular course of their operation may be used to haul diiferent trailers equipped with various numbers and different sizes and designs of electric brakes. In such a case the adjustable stop may be conveniently set to limit the travel of the lever 20 is also of value to limit the travel of the controller lever 20 to the extent indicated by the conditions of the road over which the vehicle is operated. Thus, if the vehicle is operating on good dry roads,the adjustable stop 4I may be set to permit maximum travel of the controller lever and thus permit maximum brake energization. If, however, the vehicle is operating over wet, muddy, or otherwise slippery roads, the adjustable stop 4I may be set to limit the travel of the controller operating lever to an extent such that the brakes cannot be over-energized and cause the wheels of the vehicle to slip or skid.

Electric brakes for vehicles commonly are designed for operation at six volts. Many trucks and other relatively heavy road vehicles, however, not infrequently are provided with a twelve volt battery and generator. In the case of such a vehicle equipped with electric brakes, the proper voltage may be applied to the brakes by taking a six-volt tap from lan intermediate cell of the battery. Such a procedure, however, is not particularly commendable, because it imposes a somewhat greater strain on certain cells of the battery than on the other cells. In such a case it is desirable to employ a control winding assembly of the type shown in Figs. l and 2. This control winding assembly comprises the winding form I4 with the control winding wound thereon, as described above. The form I4 is tubular, and positioned within it is a second winding form 55 on which is wound a simple resistance winding. The two winding forms I4 and 55 are supported together by the brackets I1. One terminal 56 of the resistance winding on the form 55 is connected to the terminal I5 (adjacent the full-onposition) of the control winding on the form I4. The other terminal of the resistance winding on the form 55 is connected to a binding post 51 for making connections to the battery or brakes oi the vehicle. In this manner the resistance winding on the form 55 is connected in series with the control winding on the form I4 and is always in series circuit with the vehicle battery and brakes, even when the controller lever 2D is moved to its full-on-position. The mechanical assembly described, moreover, permits this end to be achieved without requiring additional space on the base plate.

By making the resistance of the winding on the form 55 of a proper value, the effective voltage applied to the vehicle brakes may at all times be limited for that for which they are designed. regardless of the voltage actually supplied by the vehicle battery and generator. It is, of course, understood that the inner form 55 and the resistance winding thereon may be omitted entirely from the controller shown in the drawings in those cases where the voltage supplied to the brakes by the battery is approximately equal to the voltage at which the brakes are designed to operate or in any other appropriate case. In any such case, of course, the binding post 51 is connected directly to the terminal I5 adjacent the full-on-position of the control winding on the form I4.

A binding post 58 also is provided for completing connections between the controller and the vehicle battery and the brakes. The binding post 58 is connected by a suitable flexible wire 59 to the lug 29 of the contact member 26.

The control winding on the form I4 may be wound simply as a single layer coil of a continuous piece of resistance wire, or it may be wound with a plurality of sections of different sizes of resistance wire. The latter arrangement is desirable where brakes drawing considerable current are to be controlled. In such case the control winding may be wound so as to provide successively an oir-position, a section of relatively high resistance per unit of length along the form, and 'one or more additional sections of relatively and progressively less resistance per unit of length along the form. The rst section of relatively high resistance per unit of length along the form may be made of comparatively small wire having adequate current carrying capacity to carry the current required when the brakes are only partially energized. The succeeding sections of relatively less vresistance per unit of length along the form may be formed of wire of greater size to carry the relatively larger currents supplied to thebrakes when they are more fully energized. as of course occurs when the controller contact member 26 is moved along the control winding to these sections.

The controller 'described above in connection with Figs. 1 to 6 is of such design as to adapt it for use particularly on trucks and similar large and relatively heavy vehicles. In Figs. 7 and 8 there is shown a controller of modified design which may be used on light vehicles such as motorcycles. The controller shown in Figs. 'I and 8 comprises a base plate 60 on which is mounted a control winding assembly comprising a winding form 6I carrying a control winding in the form of a single layer coil 62 of resistance wire. One terminal of the coil 62 is connected to a copper band 63 forming a full-on-terminal for the controller. This terminal of the controller is connected to a wire E4 for the purpose of making suitable connections between the controller, battery, and brakes. The other end of the control winding is spaced and electrically insulated from a band S5 of metal or other suitable wearresistant material which provides an off-position for the control winding. The form 6I carrying the control winding B2 is supported by brackets E6 on and spaced from the base plate 60. A bolt 61 serves to clamp the form 6I securely in the brackets 66.

A controller operating lever 'I0 is pivotally mounted on a pin 'II which in turn is affixed to the base plate 50 in operative relation relatively to the control winding. A long arm 12 of the lever 'I0 projects beyond the base plate 60 and advantageously is formed to provide a convenient hand grip. The short arm I3 of the lever 10 extends inwardly toward the control winding 62. A contact member 14 extends from the short arm 13 into the space between the control winding 62 and the base plate 60, and there makes contact with the control winding. The contact member 14 is fastened to the lever arm 13 by rivets 15 and is insulated from the arm 13 by suitable insulating material 15. A lug 11 is provided for connecting a iiexible wire 18 to the contact arm 14 for the purpose of making connection to the vehicle batteri7 and brakes.

A torsion spring is coiled about the upper portion of the pivot pin 1I. One end 8| of this spring passes through a suitable hole in the lever 10 and advantageously projects downwardly below the lever, This downwardly projecting portion 8l of the spring' may be moved back and forth between limits defined by lugs 82 formed on the base plate, which lugsthus control and limit movement of the control ,lever .10 to the proper extent. The other end 83 of the spring 80 is held in place by a non-rotatable cap 84 mounted on a reduced upper section 85 of the pivot pin H and held thereon by a cotter pin 86.

The controller mechanism on the base plate 60 is enclosed by a suitable cover member 81 amxed to the base plate 60 by lugs 88. The base plate 60 advantageously is formed with a stamped out bracket 89 for mounting on a motorcycle handle bar `or other convenient support.

The controller shown in Figs. 7 to 8 operates in much the same fashion as the controller shown in Figs. 1 to 6. The torsion spring 8i) normally forces the controller operating lever in a direction to move the Contact member 'I4 carried thereby to the oli-position of the control Winding. Upon application of a force to the outwardly projecting arm 'l2 of the controller lever, however, the force of the spring is overcome and the contact member is moved into contact with and along the control winding 62. The electric brakes thereby are energized to an extent governed by the distance the contact member 'I4 is moved along the control winding. l

I claim:

In an electric brake controller, a base plate supporting controller operating parts, a controller lever pivotally mounted on the base plate, a stop member pivotally mounted on the base plate in position to engage the controller lever and limit the travel thereof, a cover enclosing the controller parts mounted on the base plate, a shaft connected to said stop and extending through the cover, an instantly movable stopadjustment lever connected to said shaft outside the cover, whereby the position of the stop member relatively to the controller lever may be adjusted instantly at will by manipulation of the stop-adjustment lever, and spring-actuated detent means for non-rigidly holding the stop-adjustment lever in any of a plurality of pre-selected positions, said detent means suicing to hold the stop in position and limit the travel of the controller operating lever upon application thereto of a normal force, but permitting the stop to be forced out of such selected position upon application to the controller lever cf a substantially greater than normal operating force.

WILLIAM F. PENROSE.