Feed adjusting mechanism for sewing machines

Claim 2

In a sewing machine including a machine frame, a needle feed mechanism comprising a needle bar rock frame, a pivot carried by said machine frame pivotally supporting said rock frame, a needle bar slidably carried in said rock frame, driving means in said machine frame for said needle feed mechanism including a drive shaft journaled for rotation within said machine frame, first drive means connecting said drive shaft to said needle bar for effecting reciprocation of said needle bar relative to said rock frame in response to rotation of said drive shaft, and second drive means connecting said drive shaft to said rock frame for selectively effecting a controlled rocking of said rock frame both as to feed direction and feed amplitude, said second drive means including a first grooved member connected to said rock frame and a second grooved member opposing said first grooved member, a reciprocating member having opposite end portions seated in the grooves of said grooved members, a rotary motion to reciprocating motion connection between said drive shaft and said reciprocating member, and support means for said second grooved member mounted in said machine frame for adjustment to vary the angular position of the groove in said second grooved member.

Claim 3

The needle feed mechanism of claim 1 wherein said reciprocating member includes a pin extending between said grooved members, and slide blocks pivotally mounted on opposite ends of said pin and slidably engaged in said grooved members.

Claim 4

The needle feed mechanism of claim 1 wherein a rock shaft is rotatably journalled in said machine frame, a first rock arm on one end of said rock shaft connected to said rock frame, and second rock arm on the other end of said rock shaft carrying said first grooved member.

Claim 5

The needle feed mechanism of claim 3 wherein said first grooved member is pivotally mounted on said second rock arm, and there are stabilizing means connected to said first grooved member for maintaining a constant angular relationship between the groove of said first grooved member and said machine frame as said first grooved member oscillates in response to the actuation thereof by said reciprocating member.

Claim 6

The needle feed mechanism of claim 4 wherein said stabilizing means is in the form of a parallelogram type lever arrangement.

Claim 7

The needle feed mechanism of claim 4 wherein said stabilizing means is in the form of a parallelogram type lever arrangement including a stabilizing arm extending laterally from said first grooved member as a rigid part thereof, said stabilizing arm having a free end pivotally connected to a crank member journalled in said machine frame, said crank member having a crank arm extending parallel to said second rock arm.

Claim 8

The needle feed mechanism of claim 3 wherein said machine frame includes a base, a standard, an overhanging arm and a needle head, said machine frame also including a wall separating said overhanging arm from said needle head, said rock shaft being journaled in said wall with said grooved members and said reciprocating member being disposed within said overhanging arm.

Claim 9

The needle feed mechanism of claim 1 wherein said support means is in the form of a control shaft, and means disposed externally of said machine frame for operation by an operator for readily rotating said control shaft to vary both needle feed and direction of needle feed.

Claim 10

The needle feed mechanism of claim 1 wherein said sewing machine also includes a lower work feed mechanism having adjustable feed means, and operator controlled means connected to both said support means and said work feed mechanism for simultaneously and synchronously adjusting said needle feed mechanism and said work feed mechanism.

Claim 11

The needle feed mechanism of claim 1 wherein said first grooved member is rigid with said rock frame.

Claim 12

The needle feed mechanism of claim 10 wherein said machine frame includes a base, a standard, an overhanging arm and a needle head, said machine frame also including a wall separating said overhanging arm from said needle head, said grooved members and said reciprocating member being arranged in said overhanging arm.

Claim 13

The needle feed mechanism of claim 11 wherein said support means is in the form of a control shaft journaled in said wall.

Claim 14

The needle feed mechanism of claim 11 together with a guide engaging said first grooved member for controlling the plane of movement thereof.

Claim 15

In a sewing machine including a machine frame, a needle feed mechanism comprising a needle bar rock frame, a pivot carried by said machine frame pivotally supporting said rock frame, a needle bar slidably carried in said rock frame, driving means in said machine frame for said needle feed mechanism including a drive shaft journaled for rotation within said machine frame, first drive means connecting said drive shaft to said needle bar for effecting reciprocation of said needle bar relative to said rock frame in response to rotation of said drive shaft, and second drive means connecting said drive shaft to said rock frame for selectively effecting a controlled rocking of said rock frame both as to feed direction and feed amplitude, said sewing machine also including a lower work feed mechanism having adjustable feed means, and operator controlled means connected to both said needle feed mechanism and said work feed mechanism for simultaneously and synchronously adjusting said needle feed mechanism and said work feed mechanism, said operator controlled means including a manually settable disc conveniently positioned on said machine frame and connected to a control shaft which is in turn connected to said needle feed means and said work feed means for adjusting the strokes thereof.

Claim 16

In a sewing machine including a machine frame, a needle feed mechanism comprising a needle bar rock frame, a pivot carried by said machine frame pivotally supporting said rock frame, a needle bar slidably carried in said rock frame, driving means in said machine frame for said needle feed mechanism including a drive shaft journaled for rotation within said machine frame, first drive means connecting said drive shaft to said needle bar for effecting reciprocation of said needle bar relative to said rock frame in response to rotation of said drive shaft, and second drive means connecting said drive shaft to said rock frame for selectively effecting a controlled rocking of said rock frame both as to feed direction and feed amplitude, said sewing machine also including a lower work feed mechanism having adjustable feed means, and operator controlled means connected to both said needle feed mechanism and said work feed mechanism for simultaneously and synchronously adjusting said needle feed mechanism and said work feed mechanism, said operator controlled means including a manually settable disc conveniently positioned on said machine frame and connected to a control shaft which is in turn connected to said needle feed means and said work feed means for adjusting the strokes thereof.

Claim 17

The needle feed mechanism of claim 14 wherein said manually settable disc has a screw actuated wedge type positioning mechanism.