US2022155A

US2022155A - Combination plug and switch

Info

Publication number: US2022155A
Authority: US
Inventors: Marion B Sawyer
Original assignee: Individual
Current assignee: Individual
Priority date: 1933-11-04
Filing date: 1933-11-04
Publication date: 1935-11-26
Anticipated expiration: 1952-11-26

Description

Nov. 26, 1935. M. B. SAWYER COMBINATION PLUG AND SWITCH Filed Nov. 4, 19515 INVENTOR.

MARION B \SAwYE R ATTORNEY.

Patented Nov. 26, 1935 UNITED STATES PATENT OFFICE 7 Claims.

This invention is a means for conveniently making and breaking the power circuit for an electric tool or appliance, and is particularly applicable to portable electric tools.

It is the object of the invention to provide a switch for the power circuit for an electric tool, spaced from and supported independently of the tool, so that the tool is relieved of the weight of the switch as is particularly advantageous with portable tools, and the switch is out of the Way for minimizing the liability of damaging the same, and is spaced from the operator so as to protect him against injury in the event of arcing at the switch.

It is a further object of the invention to independently support and space the switch from the tool, but to operate the switch from the tool so that the operator may conveniently control the tool.

It is a still further object of the invention to independently support and space the switch from the tool, but to adapt the switch for transportation with the tool from one power outlet to an other, so that instead of a separate switch being necessary at each outlet the one switch is adapted to control its corresponding tool at all times.

It is a still further object of the invention to readily plug in the tool at any desired power outlet, with its switch supported independently of the tool and in spaced relation therefrom so that the tool may be conveniently handled, with both the switch mechanism and the operator adequately protected.

Further objects of the invention will be readily understood from the following description of the accompanying drawing, in which:

Fig. 1 is a perspective view of a portable tool and its switch mechanism, showing the tool ready to be plugged in at a power outlet.

Fig. 2 is a front perspective view of the switch mechanism.

Fig. 3 is a rear elevation of the switch mechanism, with the housing partly broken away.

Fig. 4 is a vertical section on the line 44 of Fig. 3.

The switch mechanism may be used in connection with any electric tool or appliance but is particularly applicable to portable electric tools, and is therefore illustrated in connection with a portable electric grinder I having a shaft 2 for a grinding element 3, and provided with a usual handle 4. A cable 5 is connected to the grinder and is adapted to be plugged in at a power outlet 6, so that when the cable is plugged in the tool is readily portable within the radius defined by the length of its cable, and by disconnecting the cable from the power outlet and moving the tool to a new position and plugging in the cable at a different outlet, the tool is readily transportable and adapted for use wherever a power outlet is 5 available.

The switch for the power circuit for the tool is spaced from the tool and is supported independently thereof, so that when the tool is in use it is relieved of the weight of the switch and both the 10 switch mechanism and the operator are protected; but the switch is adapted for transportation with the tool from one power outlet to another so that each tool has is own switch and there is no necessity for a switch mechanism at each of 15 the available power outlets; and when a tool and its switch have been moved to a desired power outlet the cable for the tool is adapted to be readily plugged in, with the switch mechanism controlling the tool but spaced from and sup- 20 ported independently thereof.

For this purpose the free end of the cable 5 has a usual plug 1 adapted for quick-detachable engagement with a power outlet 6, and the switch mechanism is connected to the wires of the cable 25 5 and is preferably adjacent and supported by the plug 1, so that the quick-detachable connection 6-! mounts the switch adjacent the outlet 6 where it is out of the way and spaced from the tool by the length of the cable, and with the tool 30 relieved of the weight of the switch. When the plug 1 is withdrawn from outlet 6 for moving the tool to another outlet, the plug and switch are preferably suspended as a unit from the free end of the cable 5, so that the entire assembly may 36 be readily transported and again connected to the power circuit by simply plugging in at an other outlet.

As an instance of this arrangement, the switch is preferably mounted on one face of a plate or 40 support I 0 with the plug I projecting from the opposite face of this plate and the cable 5 extending from the end of the plate. A housing ll may enclose the switch and is preferably detachably secured to the margin of plate l0, and may 45 cooperate with the plate for clamping the end of the cable relative to the switch assembly. The switch may be a'usual magnetic relay switch, comprising an electro-magnet l2 having a normally spring retracted armature l3 carrying con- 50 tact strips H which are adapted to bridge spaced contacts l5|6; and the elements of the switch are preferably mounted on a base H, which is in turn supported on plate Ill, preferably in spaced relation therefrom as shown at I8. 55

The plug 1 and the outlet 6 may be of usual construction, the plug comprising contact prongs l9 projecting from a base 20 which is mounted on plate in, and the cooperating outlet having slots 2i adapted for detachable reception of the contact prongs. The outlet 6 is shown provided with four slots, three for the lines of the power circuit and the fourth a ground connection, and the plug 1 has the same number of prongs connected to corresponding wires 22 of the cable 5. The switch is in circuit between the wires 22 and the prongs [9, the connections being made through an opening 23 in the plate which communicates with the open bore of base 20 and with the space l8 beneath the base I1, and the prongs l9 have terminals 24 and the contacts l-IS have terminals 2526 for making the necessary connections.

In order to securely clamp the end of cable 5 between the plate i0 and the housing I I, the end of the plate may form a recess 30 adapted to receive the cable with the end wall of housing H forming a cooperating recess 3| adapted to fit over the cable; and a split collar may be clamped on the cable, with one half of the split collar integral with and projecting from the housing I l as shown at 32, and the other half of the split collar comprisin a separate element 33 which is adapted for detachable assembly with the collar element 32 by means of screws 34.

The magnetic relay switch is preferably controlled from the tool so that the control is read ily accessible to the operator, and for this purpose the cable 5 in addition to the four wires 22 for the power circuit and the ground connection, also carries a pair of wires 36 which are connected to a switch 3'! mounted on the tool. This switch may be a. usual thumb switch mounted on the handle 4; and the opposite ends of wires 36 are connected to the terminals 38 for the winding of the magnet 12, the connections being such that the thumb switch 31 controls the energizing and tie-energizing of the magnet l2, for making and breaking the power circuit at the contacts [5-4 6.

The tool is thus readily controlled from the handle of the tool, at a point convenient to the operator, but the power circuit is made and broken not at the tool but at the opposite end of the cable, and the switch for the power circuit is supported not by the tool but by the plugged-in connection B--=', and the magnetic switch is a unitary part of the plug '1, whereby the entire assembly may be readily transported and plugged in at any usual power outlet.

I claim:

i. In combination, a support, an electric cable, an electric contact plug at one face of the support, a switch at the opposite face of the support in electric circuit with the plug and the cable, and a housing mounted on the support and enclosing the switch, the housing and support cooperating to clamp the cable therebetween.

2. In combination, a support, an electric cable, an electric contact plug carried by the support, a switch carried by the support and in electric circuit with the plug and the cable, and means for clamping the cable relative to the support.

3. In combination, a support, an electric cable, an electric contact plug at one face of the support, a switch at the opposite face of the support in electric circuit with the plug and the cable, a

control circuit for the switch, and an electric 5 switch for the control circuit, said switch being re mote from the support.

4. In combination, a portable electric cable adapted for connection at one end to a portable electric tool, an element of an electric contact means, which comprises quick-detachable cooperating plug and socket elements, at the opposite end of the cable and portable with the cable, a relay switch portable with the cable and remote from the first mentioned end of the cable and in electric circuit with the cable and with said element of the electric contact means which is at the first mentioned end of the cable, a control circuit for the relay switch, and an electric switch for the control circuit, said switch being remote from the relay switch.

5. In combination, a portable electric cable adapted for connection at one end to a portable electric tool, a support at the opposite end of the cable and portable with the cable, an element of an electric contact means, which comprises quickdetachable cooperating plug and socket elements, mounted on the support, a relay switch mounted on the support and in electric circuit with the cable and with the element of the electric contact means which is mounted on the support, a control circuit for the relay switch, and an electric switch for the control circuit, said switch being remote from the relay switch.

6. In combination, a portable electric cable adapted for connection at one end to a portable electric tool, a support at the opposite end of the cable and portable with the cable, a relay switch mounted on the support, the cable having electrical connection with one side of the relay switch, 40 means for securing the cable relative to the support, an element of an electric contact means, which comprises quick-detachable cooperating elements, having electrical connection with the other side of the relay switch and being portable with the cable, a control circuit for the relay switch, and an electric switch for the control circuit, said switch being remote from the relay switch.

'7. In combination, a portable electric cable adapted for connection at one end to a portable electric tool, a support at the opposite end of the cable and. portable with the cable, a relay switch mounted on the support, the cable having electrical connection with one side of the relay switch, means independent of said electrical connection for securing the cable relative to the support, an element of an electric contact means, which comprises quick-detachable cooperating elements, having electrical connection with the other side of the relay switch and being portable with the cable, a control circuit for the relay switch, and an electric switch for the control circuit, said switch being remote from the relay switch.

' MARION B. SAWYER.