Kress-elektrik Gmbh & Co., Elektromotorenfabrik

Kress-elektrik Gmbh & Co.

Kress-elektric Gmbh & Co. Elektromotorenfabrik

Firma Kress Elektrik Gmbh & Co.

Willy Kress

Alfred Binder

Josef Seifert

For a manually operated trigger or switch lever for electric appliances, particularly hand-held electric appliances, such as a portable drill, screwdriver, drilling hammer, grinder, right angle grinder, etc., which, when the appliance is started up, is shifted by the action of pressure applied by the operator and, at the same time, brings about switching processes (switching on and off, accelerating, switching over, reversing) in the appliance, at least the surface of the trigger, which comes in contact with the fingers or a portion of the hand of the operator when pressure is exerted, has at least one elastomeric coating.

Manually operated trigger or switch lever for electric appliances

Manually operated trigger or switch lever for electric appliance

For the trickle resin impregnation of mainly electrical windings or of other components, electric motors, etc., containing electrical elements, a curing agent-free trickle resin is allowed to leave separately from an outlet opening to form a jet, which is flowing onto the object that is to be impregnated. Before the jet strikes the object, a curing agent may be sprayed onto the jet surface of the flowing trickle resin, so that trickle resin, mixed with curing agent, comes into contact exclusively with the object to be impregnated and not with any other object.

Apparatus for impregnation of an object with curable resin

Trickle resin impregnation by mixing resin in free fall with a curing

An electric motor comprises bracket shaped end plates having extensions that lead directly to the stator and are connected to the stator by introducing the extensions into grooves. The motor includes a layered arrangement of components on the collector-side, comprising a carrier plate with a punched grid pattern forming the electric wiring. The grid pattern, together with the carrier plate, carry brush holders. Next in the axial direction is a switching ring bridging preselected line connections of the grid pattern by means of short circuiting bridges, and which is rotatably seated in a central recess of a mounting plate provided on the end plate. All connections can be fabricated by simple pressing and plugging and the motor is suited for fully automatic assembly operations.

Universal electric motor with a switch ring mounted adjacent the brushes

In the case of a universal electric motor for any kind of drive, with a stator package, a rotatably mounted rotor with commutator, as well as end shields on both sides that also constitute the bearings for the rotor and a switching ring that can be rotated through predetermined angular amounts and carries the (carbon) brushes, it is proposed to insert into the end shield A a closely fitting anchor block that serves for locking together the two end shields with the intervening stator package; further, the switching ring can be mounted on an external annular end face of the end shield B that also carries the switching strips or switching rails needed for switching between clockwise and counter clockwise rotation, complete with contact areas situated in the plane of the annular end face and suitable for axial contacting, the said contact areas making contact with other axial contact areas on the switching ring to establish connections with the carbon brushes.

Universal electric motor

For the purposes of assembling an electric tool, and especially an electric hand tool such as, for example, a hand drill, a grinder or a sabre saw, it is proposed to use modular components that are to be axially inserted into and connected with each other. The components comprise a self-contained electric driving motor that supports the rotor shaft in a centered position by means of end shields on both sides that are rigidly fixed to the stator, a self-contained gearing head that is fixed to the motor, and at least a partially tubular, single piece main housing that accommodates the driving motor and the gearing head, an electric circuitry module inserted into the main housing, and a rear cover for the housing.

Electric tool

It is proposed to obtain a switching device for the electrical switching (i.e. switching on and off or reversing the direction of rotation) of electric tools, especially electric hand tools such as drills, grinders and the like, by mounting a rotatable setting ring on the outer cylindrical housing of the electric tool and positioning it opposite the end shield at the B-end of the electric motor inside the housing in such a manner that inwardly pointing projections of the setting ring will grip a plate or switching ring on the electric motor and will cause the said plate or switching ring to perform a slave motion for switching the electric motor on and off or reversing its direction of rotation whenever the external setting ring is subjected to a manual rotation. It is also possible and advantageous to provide an automatic return to bring the setting ring back into its initial position; the mechanism, realized with biasing springs, comprises a releasable locking device that will maintain the setting ring in its deflected position.

Switching device for the electric switching of electric tools

A power-driven screwing tool comprising an electric drive motor, an adjustable depth stop, a drive shaft receiving the screwing tool and adapted for being displaced relative to the depth stop. Between the drive motor and the drive shaft, a first clutch (jaw clutch) transmits the driving torque by form-locking engagement, while a second clutch responds to the predetermined screwing depth and acts to release the form-locking engagement of the first clutch by comprising a transverse pin being engaged or disengaged by a guide pocket whose bottom surface extends at a certain inclination relative to the longitudinal axis of the drive shaft.

Power-driven screwing tool

In connection with a conversion set for a portable circular saw, which latter comprises a housing, an associated electric drive motor with output shaft and, if necessary, also a gear, and at least one handle, it is proposed to attach to the basic unit remaining after removal of the circular saw blade a chain-saw adapter attachment, to convert the portable circular saw in this manner into an electric chain saw and to secure the chain-saw adapter attachment in place by means of mechanical stops provided on a main bearing plate and coacting with the gear housing of the circular saw and, in the axial direction, by tightening a screw upon the output shaft of the circular saw projecting through the drive pinion for the saw chain.

Conversion set for a portable circular saw

A connecting arrangement for a machine tool in which a driving element and a driven component are constrained from relative twisting by guide pins and are further coupled to transmit torque therethrough. The coupling mechanism is provided with an external release lever so that the faces of the driving and driven elements are in complete registry when so coupled.

Growing community of inventors

Bisingen, Germany

Willy Kress