United States Patent 3773988

A switch with two identical interchangeable blades which permit ease of contact replacement and extended switch life is shown. Each blade has a top and a bottom contact so that when assembled in a housing the top contact of one is aligned with the bottom contact of the other. By simply interchanging blades the spare contact may be put into use thus offering quick and inexpensive contact replacement. Other features include means of stacking the switches with each switch in the stack providing a cover for the one before it thus requiring only one cover for the whole stack.

Application Number:
Publication Date:
Filing Date:
Primary Class:
Other Classes:
200/6BB, 200/280
International Classes:
H01H11/00; H01H19/64; (IPC1-7): H01H21/12
Field of Search:
View Patent Images:
US Patent References:
3359392Rotary switch1967-12-19Heath
3313905Switch and terminal assembly for selectively controlling dynamoelectric machine winding circuits and the like1967-04-11Zagorski
2782287Switch mechanism1957-02-19Smith

Primary Examiner:
Scott J. R.
What is claimed is

1. An electrical switch of the hard contact, flexible blade type comprising, in combination:

2. The invention according to claim 1 wherein said blades are identical in construction.

3. The invention according to claim 2 wherein each of said blades includes a bent-over portion at the ends opposite said one ends, said bent-over portion being engaged by said supports to hold said opposite ends in spaced relation.

4. The invention according to claim 3 wherein said blades are essentially parallel to one another when held by said supports.

5. The invention according to claim 4 wherein said one end of one of said blades is engaged by said actuating means and moved toward said one end of the other blade, with the opposite ends of each blade remaining stationary, whereby the engaged blade is flexed, moving said one end thereof out of parallel with said one end of the other blade during actuation.

6. The invention according to claim 5 and further including electrical connecting clips held by each of said supports for electrical contact with the ends of said blades held by said supports.

7. The invention according to claim 5 wherein said actuating means comprises a member mounted on said housing for pivotal movement with respect thereto.


This invention relates to switches in general and more particularly to an improved switch with interchangeable blades.

It is well known in the art the switch contacts are subject to wear due to arcing, etc. Attempts have been made to obtain switch action which will minimize these effects. Still, ultimately contacts will have to be replaced. This of course is a factor in the cost of switch operation. It also means that replacement contacts must always be kept on hand and, if the whole switch is not to be replaced that the switch be designed so that contacts may easily be replaced. In some switching operations failure of the switch must be remedied as quickly as possible. For example switches in highway traffic light controlls cannot long be out of service without undesirable results. In such systems repairs must be made quickly. One approach to a quick switch contact replacement is shown in U. S. Pat. No. 2,230,737. One of the switch contacts is made rotatable with two contact surfaces so that, when excessive wear occurs the one contact need only be rotated to the other position.

Although this device goes a long way toward solving problems of contact replacement it does have drawbacks. When the second side is worn both contacts will have to be replaced. Since the contacts are both constructed differently, two types of contact must be manufactured and kept on hand. In addition the type of design employed is bulky and complete contact replacement relatively time consuming.


The switch of the present invention uses two identical interchangeable blades each having two contacts. This means only one type blade (or contact) need be manufactured and kept on hand. Also interchanging the blades completely restores the switch to its original condition, i. e., both contacts are brand new. The switch is designed for compactness and ease in changing blades. Additionally, any number of switches may be stacked together with each additional switch providing a cover for the previous switch thereby requiring a cover only on the last switch. Even in situations where quick repair is not essential the switch of the present invention effectively doubles switch life through providing a spare set of contacts which can be put into use in a simple manner.


FIG. 1 is a perspective view of a preferred embodiment of the switch of the present invention.

FIG. 2 is an elevation view of FIG. 1.

FIG. 3 is a plan view of two of the switches of FIG. 1 connected to-gether.


A perspective view of a preferred embodiment of the uncovered switch is shown in FIG. 1 and an elevation view in FIG. 2. Each switch blade 11 is essentially a thin flat piece of a resilient conductive material and contains a flat contact 13 on the top and a rounded contact 15 on the bottom. The ends 16 of the blades 11 are bent to allow attachment of a connecting clip 19. The contacts are slid into a switch housing 17 which may be cast in plastic or a similar material. The housing is constructed such that projections 21 (shown on FIG. 2) restrain movement of the switch except as required for switching action. The blades are arranged so that contact 15 on the bottom of the upper blade 11 will be aligned with contact 13 on the top of the lower blade 11. Also formed into housing 17 is a pin 25 on which an actuator 23 is placed for rotation. A projection 26 in the housing limits the travel of actuator 23.

If actuator 23 is pushed upward the contact 13 of the lower blade 11, guided by a projection 27 on the housing 17, will contact the contact 15 of upper blade 11. Connection of the switch into a circuit is made by attaching clips 19 on the ends of wires 20 to the bent ends 16 of the blades 11. Holes 29 are provided to allow a plurality of switches to be fastened together as shown on FIG. 3.

FIG. 3 shows two switches 33 and 31 and a cover 35 held together by bolts 37 and nuts 39. As can be seen, switch 31 provides the cover for switch 33. In like manner any number of switches may be stacked with only one cover 35 required.

When the contacts 13 and 15 of any of the switches are worn it is only necessary to unfasten nuts 39, disconnect clips 19 are interchange the two blades 11. As shown on FIG. 2, contact 13a would then be on the bottom and 15a on the top. In this manner the switch may be quickly restored to its original condition.

Thus a switch with interchangeable contacts which permits quick repair and effectively doubles the switch life before contact replacement is required has been shown. Although a specific embodiment has been shown it will be evident to those skilled in the art that various modifications may be made without departing from the spirit of the invention which is intended to be limited solely by the appended claims.