US1975521A - Pedal switch - Google Patents

Description

. G. sTAUDE PEDAL Y SWITCH oct. 2, 1934.`A

Filed Nov; 22, 195o 2 Sheets-Sheet 1 E. G. STAUDE PEDAL SWITCH Oct. 2, 1934.

Filed Nov. 22, 1950 2 Sheets-Sheet 2 Patented Oct. 2,1934

UNITED STATES PATENT OFFICE I PEDAL SWITCH 9 Claims.

This invention pertains to improvements in pedal operated switches, which can be used for controlling dual-powered brake mechanisms such, for example, as described in my copending d application for F'luid power controlling mecha.-

nism, Serial Number 375,846, led July 3, 1929 and such as described in my copending application for Pedal switches, Serial Number 470,060, filed July 23, 1930. In both of the aforesaid apl@ plications, electrically operable means is provided for assisting brake-applying operation, and it is among the objects of this invention to provide a switch winch will control the circuit to this means for assisting the braking operation, to

.i start the motor if the pedal moves in brake- -applying direction, and to stop the motor when the pedal moves even slightly in a reverse direction, and to accomplish this result without the use of an oscillating pedal switch which is located on the pedal step as in application Serial No. 470,060. Although the construction disclosed in the last mentioned application has been found practicable for the intended use, it is dimcult to apply without some modiiication of the Q5 existing structure. In application, Serial No. 375,846, the circuit is not opened to stop the motor until a maximum 'return movement ofthe pedal has taken place. This is objectionable because it may happen that the pedal sticks, and does not fully complete its brake-releasing stroke and thus the circuit is not opened to stop the motor. In any event, the motor cannot be stopped until the pedal has completed its stroke, and there results an unnecessary and excessive current consumpl'i tion, for example while on a hill, or while waiting for a go" sign.

The construction described in my application, Serial No. 470,060, permits the proper opening or closing of the electric circuit, and, therefore, the

f starting or stopping of the motor, but frequently the driver does not think oi saving current and, therefore, frequentlypermits the motor to run,

, or maintains the switch in closed position when it is unnecessary.

M It has been observed in the uid power con-= trolling mechanism of application Serial No. 375,-

846, that after the fluid pressure is once set up 'against the piston, it will be maintained for a 5@ tconsiderable period, even though the motor ceases ,to operate. It is, therefore, an object herein to dprovide a switch so operable by the pedal, that ,advantage can be taken of this period o f-pressure maintenance to conserve current, an opening of ,5 the switch taking place in case the operator eases (Cl. 20o-59) up on the pedal as he often unconsciously does to relieve muscular strain.

An object is to so construct the switch and so connect it in the system that on slight pedal depression electrical contact will be made, and so that on continued depression this contact-will be maintained, and so that after the pedal has been depressed to any given degree and if a slight reverse movement takes place due to less muscular action on the part of the operator, the contact will be immediately broken, but can be again made substantially instantly if the pedal is again pushed forwardly. This arrangement allows for what is known as inching", the con tacts being so arranged that a retrograde or reverse motion of the pedal substantially iins mediately opens the circuit and a forward nica tion substantially immediately closes it, what ever the positions of the pedal, that is whateverl the position other than its initial non-brakeapplying position, in which the vcircuit is always open. Thus, the outstanding advantage here is that the switch is always closed at any point in the brake-applying pedal stroke, regardless of the position of the pedal, and is always open directly i that the pedalrecedes or reverses its movement even though the distance moved be one-eighth of an inch.

Features of the invention include all details of construction, as well as the broader ideas ci means, along-with the particular application in a braking system.

It will be understood that the switch structure per se is capable of other uses than that shown, although the switch in combination with electrically operable means for assisting in a brakeapplying operation is also claimed.

Features and advantages of the invention willi be pointed out in the description of the drawings forming a part of this application, and in said drawings Figure l is a section through an automobile floor showing the device in elevation, in asso= ciation with an electrically operable means for assisting brake-applying operation;

Figure 2 is a vertical transverse section on line 2--2 showing how a portion of the device is connected to the engine, and one arrangement for grounding the circuit;

Figure 3 is a vertical longitudinal section of the pedal switch showing its connection with the pedal and the position of the :door board with relation to the pedal;

Figure 4 is a sectional elevation substantially similar to Figure 3, showing the pedal depressed and the contact members in closed circuit position;

Figure 5 is a section through the brake lever on line 5-5 of Figure 4 showing the means for pivotally attaching the switch to the pedal;

Figure 6 is a longitudinal section showing a modified form; and

Figure 7 is a section on line 7-7 of Figure 6.

In the drawings, 2 represents the ordinary floor board of a motor,- car through which the usual foot pedal extension operates. The foot pedal 3 is pivoted at 4, and is connected to an electrically operable means, generally indicated at 6, adapted to assist in the brake-applying operation, see copending application Serial No. 375,846. The brake mechanism is not shown, but element 5 connects the mechanism 6 with that mechanism. 7 represents the conventional type of motor having the usual crank case ange bolts 8. Secured to the upper part of the foot pedal 3 by a U-shaped clipv 10, is a shaft block 11, clamped to the pedal by lthe nuts 12 threaded on the legs of the clip.I The block 11 has an 'ex-I tension 13 'on which is mounted a cap of insulating material 14. I'he cap has a threaded connection with` the end of the sleeve 15, which sleeve is also of insulating material', preferably of the type known as hard fiber. The opposite end of the sleeve 15 has a cap 16 of conducting material, in threaded engagement therewith, or detachably secured, which'cap provides a bearing 17through which the bar 18 slides. The bar 18 as a' guide, projects through the sleeve and both caps, and protrudes as shown. The member 14 provides a bearing 19. A metal conductor or contact 20, preferably of copper, is insulated from the bar 18 by a sleeve 21. A binding post 22 has threaded connection with the contact 20 at 23, and cable 24 connects this'binding post with binding post 25 (see Figure 1) of the power mechanism 6.

The lower end of the rod `18 has a threaded connection with the eye 27, see Figure 2. A bolt 28 passes through the eye and has a shoulder 31 which engages the' angle plate or bracket 29. A clamping nut 30 draws the shoulder against the angle plate, and rigidly secures the bolt in outstanding position. 'I'he opposite member of the angle plate is secured to the engine by one of the ange bolts 8. This is a feature. In order to form an anti-rattling joint, a spring 32 bears against the eye, and against a washer 33 which engages the head of the bolt 34', thus forcing the eye against the angle plate but permitting a hinging movement, and at the same time establishing a ground for the electric circuit.

A spool-shaped contact member 35 is housed by the sleeve 15, but is not connected thereto, and is provided with a terminal recess 36. Within this recess is a iiat spring 37 which bears against the spool 35 and against the rod 18 to establish a friction resistance, or a yieldable friction connection. The member 35 can engage at point 38 with -contact 20, when the sleeve is translated by the pedal as the pedal moves in brake-applying direction. This is possible because members 16,35, 21 and 14 slide on the lbar 13. The member 14 is pivoted at the point 13, and, therefore, the frictional resistance of the spring 37 against the shaft 18 causes the contact 35 to remain stationary until contact 20 engages it. This engagement closes the circuit to the motor. This circuit-closed position is shown in Figure 4. Just as soon as pedal motion is reversed, even if the movement is as small as one-eighth of an inch, sleeve 15 is moved in the opposite direction, and 20 moves away from 35 instantly opening the circuit and'stopping the motor. Whatever the positionlof thev pedal, the slightest downward movement closes the circuit and starts the motor, and the slightest upward movement breaks the circuit and stops the motor.

By the use of this switch and by connecting it as shown in thesystem, with the electrically operable means for assisting brake-applying operation, the driver can automatically maintain the pressure and hold the car under brake control, with the motor circuit open and the motor stopped. Directly that additional power is required, he substantially unconsciously again presses a little harder on the pedal which instantly closes the switch and starts the .motor until itrecovers its pressure. It will be noted that this pressure is only lost by slight seepage past the pump gears. Directly that the pressure is again suiciently raised,l the driver almost unconsciously permits the pedal to retract sutilciently to again open the motor circuit. In this way a substantialreductin in current consumption is obtained, and in practice actually onethird of the amount of current is required, as is required in a system in which this present invention is not used, or in which the control is notl substantially automatic in the manner above set forth. y

`It will be noted that the housing 15. is made of insulating material and that the contact 20 is insulated from the rod and that the element 20 and the cap elements 16 form stops which alternately engage the element 35 in a manner to move it alternately in opposite directions. It will be further noted that there is a lost motion effect. The sleeve 15 houses the entire mechanism, and the detachable arrangement of the caps permits of quick assembly.

In Figure 6 is shown a modified form of switch,

41 is made in two pieces, as best shown in Figure- 7 and is held in yieldable frictional contact with theb rod 18 by a coil spring 42 which has a constricting action. One of the advantages of this construction is that when the conical surface 39 engages the conical surface 40, there is aconstricting action on the element 41, which increases the frictional contact between the member 41 and the bar 18; a kind of wedging action. On reverse pedal motion, this pressure is decreased and friction is then supplied only by thespring 42.

'I'he spring 42 may be of any conventional design that is capable of holding the two members 41 into frictional contact with the shaft 18.l In actual practice, the arcing of this switch is not suincient to cause the surface to become pitted to any appreciable extent, particularly if the area of Vcontact is sumciently great. I1' there should be some difliculty in this' respect, the element 15a can merely be inverted and lled or partly lled with oil following the ordinary practice for overcoming such diiiiculties. The pedal switch just described may be modified in many ways without departing from the spirit of this invention, since the invention consists` largely in making a switch device that is controlled by the direction of movement of the pedal. In view of this, there is no intention of being entirely coni-lned to the speciflcstructure, since that may be modiled in various ways without departing from the invention. The construction is applicable to any type of existing pedal without drilling any openings, and the unit may, therefore, be applied to any existing automobile in a few minutes time. Aside from the value of current saving, the fact that it gives the operator automatic control and that it is inexpensive in construction and may be quickly applied to existing cars, is of utmost importance and of great value, especially when used with devices similar to that shown in the drawings. Instead of grounding the circuit on the motor, as shown in Figure 2, member 18 may be insulated f om the bolt 28, and thelive wire be connected to the member 18 and the power unit 6 grounded. This is mentioned because anyone skilled in the art could easily use other types of wiring diagrams.

I claim as my invention:

1. A rod, a contact sleeve having a yieldable friction and conducting connection with the rod, a sleeve directly slidable on the rod and housing the contact and also housing a contact insulated from the rod and adapted to engage the other contact when the sleeve is translated and when so engaged to translate the same, said sleeve having means adapted to entrain the friction contact in an opposite direction after separation of said contacts, said means comprising a cap detachably secured to said sleeve.

2. In combination with a brake pedal of an automobile, a switch structure having a rod pivotally supported independently of the pedal, a rst contact having a yieldable frictional connection with said rod, an insulating sleeve slidable on the rod and having a contact movable therewith and insulated from the rod, said sleeve being pivoted to the pedal, the contacts being so related that they are in open circuit position when the pedal is fully retracted and so related that they assume circuit making position when the pedal is depressed and remain in contact as the pedal motion continues in the same direction, and so related that on reverse movement of the pedal the contacts assume and are maintained in circuit open position during continued reverse motion.

3. In combination in an automobile an engine, a brake pedal, a support pivoted to the engine, a switch structure including contact members movable upon the support, and means by which the members are controlled by the pedal to be substantially instantly moved to closing position when the pedal is depressed, and so that instantaneous opening or closing of the switch takes place in correspondence to the direction of pedal motion whatever the position of the pedal between its motion limits.

4. In combination with an automobile a brake pedal, a support independently pivoted, a housing slidable on said support and pivoted to the pedal and having therein first and secondswitch contact members separately slidable upon the support, the rst member being movable relative to the -housing and the other being movable with other in a direction away from their pivotal points, first and second switch contact members separately slidable upon the support, means pivoting one of the switch members to the control member, and means carried by that switch member for entraining the second switch member when the control member moves in one direction, the parts being so associated that movement of the control member in an opposite direction closes the switch and the elements being so related as to be substantially instantly moved from one control position to another in correspondence to motion of the control member, whatever the position of the control member between its motion limits.

6. In combination, a pivoted control member, a support independently pivoted, the pivotal axes of the support and control member being substantially parallel, first and second switch contact members separately slidable upon the support, means pivoting one of the switch members to the control member, and means carried by that switch member for entraining the second switch member when the control member moves in one direction, the parts being so associated that movement of the control member in an opposite direction closes the switch, and the elements being so related as to besubstantially instantly moved from one control position to another in correspondence to motion of the control member, whatever the position of the control member between its motion limits.

7. In combination an automobile, a brake pedal, a rod pivoted to the automobile forwardly of the pivotal point of the pedal, an insulating housing pivoted to the pedal and slidable on the rod, a. rst contact carried by the housing out of electrical contact with the rod, a second contact slidable on the rod in electrical contact therewith and engageable with the rst contact, means frictionally resisting but permitting sliding motion of said second contact on the rod, said contact being limited for slight reverse motions by the housing and first contact, and a circuit which is completable through the first contact, rod, and second contact.

8. A pedal, a rod pivoted independently of the pedal, an insulating housing pivoted to the pedal and slidable on the rod, a first contact carried by the housing out of electrical contact with the rod, a second contact slidable on the rod in electrical contact therewith and engageable with the first, contact means frictionally resisting but permitting sliding motion, said contact being limited for slight reverse motions by the housing and lirst contact, the pivotal points of the pedal, rod and housing being so related that reverse sliding motions of the housing on the rod are obtainable conformably to corresponding and slight pedal motions.

9. In combination with an automobile, a brake pedal, a support of conducting material having a conducting pivotal connection with a conducting part of the automobile, an insulating element slidable on the support and pivoted to the pedal,

va first contact xed for motion with the insulating element, a second contact movable relatively to said insulating element and support and in conducting relation with said support, said contact being limited for slight reverse motions by the insulating element and the first contact, and a circuit which is completed through the contacts, conducting support Aand said conducting part of the automobile.

EDWIN G. STAUDE.

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