Power driven positioning apparatus with force dependent shut-off, to position an engagement element against an abutment

Claim 2

Power driven positioning apparatus with force-dependent shutoff, to position an engagement member (1) against an abutment (1'') comprising a housing (15); a spindle (3) passing through the housing and adapted to be connected to the element to be positioned with predetermined force against the abutment; a motor (6) in driving engagement (4, 5) with the spindle (3), the spindle being subject to axial excursion when the element impinges on the abutment; bearing means (8, 9) axially spaced on the spindle and journalling the spindle, the bearing means being axially movable with the spindle upon axial excursion thereof; means (10) located in the housing guiding the axial movement of the bearing means; spring means (12, 13, 14) having projecting portions (12, 13) and an attachment portion (14), the projecting portions extending over the bearing means and holding said bearing means between the projecting portions in pre-determined axial position, the attachment portion being secured to the housing; and switch means (16, 17) engageable by the projecting portions of the spring means upon deflection of the spring means due to engagement of the bearing means with the projecting portions of the spring means upon axial excursion of the spindle.

Claim 3

Power driven positioning apparatus with force-dependent shut-off, to position an engagement member (1) against an abutment (1'') comprising a housing (15); a spindle (3) passing through the housing and adapted to be connected to the element to be positioned with predetermined force against the abutment; a motor (6) in driving engagement (4, 5) with the spindle (3), the spindle being subject to axial excursion when the element impinges on the abutment; bearing means (8, 9) axially spaced on the spindle and journalling the spindle, the bearing means being axially movable with the spindle upon axial excursion thereof; means (10) located in the housing guiding the axial movement of the bearing means; spring means (12, 13, 14) having projecting portions (12, 13) and an attachment portion (14), the projecting portions extending over the bearing means and holding said bearing means between the projecting portions in pre-determined axial position, the attachment portion being secured to the housing; and switch means (16, 17) engageable by the projecting portions of the spring means upon deflection of the spring means due to engagement of the bearing means with the projecting portions of the spring means upon axial excursion of the spindle.

Claim 4

Power driven positioning apparatus with force-dependent shut-off, to position an engagement member (1) against an abutment (1'') comprising a housing (15); a spindle (3) passing through the housing and adapted to be connected to the element to be positioned with predetermined force against the abutment; a motor (6) in driving engagement (4, 5) with the spindle (3), the spindle being subject to axial excursion when the element impinges on the abutment; bearing means (8, 9) axially spaced on the spindle and journalling the spindle, the bearing means being axially movable with the spindle upon axial excursion thereof; means (10) located in the housing guiding the axial movement of the bearing means; spring means (12, 13, 14) having projecting portions (12, 13) and an attachment portion (14), the projecting portions extending over the bearing means and holding said bearing means between the projecting portions in pre-determined axial position, the attachment portion being secured to the housing; and switch means (16, 17) engageable by the projecting portions of the spring means upon deflection of the spring means due to engagement of the bearing means with the projecting portions of the spring means upon axial excursion of the spindle.

Claim 5

Apparatus according to claim 1, wherein the switch means comprises a pair of electrical switches (16, 17) having respective operating elements (16a, 17a) each, located in the housing for engagement of the operating elements by the projecting portions of the spring means.

Claim 6

Apparatus according to claim 1, wherein the guide means guiding the bearing means are slightly shorter than the distance between the projecting portions of the spring means.

Claim 7

Apparatus according to claim 3, wherein the bearing means comprises stationary and rotary races, and the spring means locate the stationary races in axial position with respect to the spindle within the housing.

Claim 8

Apparatus according to claim 3, wherein the bearing means are ball bearing means and comprise grooves formed in the spindle, balls running in the grooves, and outer races carried along in axial direction upon axial excursion of the spindle, and hence the balls in the grooves of the spindle, said outer races being resiliently compressed against each other by the projecting portions of the spring means.

Claim 9

Apparatus according to claim 1, wherein the housing comprises a pair of substantially symmetrical shells having a separating plane passing through the axis of the spindle.

Claim 10

Apparatus according to claim 6, wherein the motor has an outer circumference form-fitting into the housing.

Claim 11

Apparatus according to claim 1, wherein the spring means comprises a U-shaped leaf spring, the attachment portion forming the base portion of the U-shaped leaf spring and being located in engagement with the wall portions of the housing, the projecting portions being formed by the leg portions of the U-shaped leaf spring.

Claim 12

Apparatus according to claim 1, wherein the engagement means (1) is non-rotatable and subject to axial travel upon rotation of the spindle (3), said engagement element being formed with a rack surface; and a pinion (19) engaging the rack surface.