Packaging machine and method

An apparatus for packaging products using continuous first and second webs of flexible packaging material, the apparatus comprising:

• a packaging station comprising a pair of rollers forming a nip through which the first and second webs with a product disposed therebetween are advanced in a longitudinal direction such that the webs are adhered to each other and envelop the product;
• a web drive system operable to advance the first and second webs to the packaging station, the first web being advanced along a generally horizontal path from a product placement location at which the product to be packaged is placed onto the first web, toward the packaging station;
• a light source configured to pass light at least partially through the first web;
• a product-sensing detector adjacent the first web at or downstream of the product placement location and upstream of the packaging station such that the product-sensing detector is in a direct path of the light passing through the first web when no product is present on the first web, the direct path being blocked by the product when present on the first web, the product-sensing detector being operable to detect the difference in light when the direct path is not blocked compared to when it is blocked and to provide a signal of a first type when said path is not blocked and of a second type when said path is blocked, indicating the presence of a product to be packaged;
• and
• a controller connected with the web drive system and the product-sensing detector, the controller being operable to cause the web drive system to advance the first and second webs toward the packaging station only when the signal from the product-sensing detector is of the second type.

An apparatus for packaging products using continuous first and second webs of flexible packaging material, the apparatus comprising:

• a packaging station comprising a pair of rollers forming a nip through which the first and second webs with a product disposed therebetween are advanced in a longitudinal direction such that the webs are adhered to each other and envelop the product;
• an infeed conveyor belt for conveying the products to the packaging station from a product placement location at which each product to be packaged is placed;
• a web drive system operable to advance the first and second webs to the packaging station;
• a product-sensing detector adjacent the infeed conveyor belt at or downstream of the product placement location and upstream of the packaging station such that the product-sensing detector has a direct line of sight to the infeed conveyor belt when no product is present on the infeed conveyor belt, the line of sight being blocked by the product when present on the infeed conveyor belt, the product-sensing detector being operable to detect a characteristic of the infeed conveyor belt distinct from the products being packaged and to provide a signal of a first type when said characteristic is detected and of a second type when said characteristic is not detected, indicating blockage of the line of sight;
• and
• a controller connected with the web drive system and the product-sensing detector, the controller being operable to cause the web drive system to advance the first and second webs toward the packaging station only when the signal from the product-sensing detector is of the second type.

A method for packaging products using continuous first and second webs of flexible packaging material, comprising the steps of:

• advancing the first web along a generally horizontal path toward a packaging station, and advancing the second web toward the packaging station such that the webs at the packaging station are in overlying relation and are sealed together with a product enclosed therebetween;
• receiving the product to be packaged onto the first web at a product placement location upstream of the packaging station;
• and
• providing a product-sensing detector adjacent the first web at or downstream of the product placement location and upstream of the packaging station such that the product-sensing detector has a direct line of sight to the first web when no product is present on the first web, the line of sight being blocked by the product when present on the first web, the product-sensing detector being operable to detect a characteristic of the first web distinct from the products being packaged and to provide a signal of a first type when said characteristic is detected and of a second type when said characteristic is not detected, indicating blockage of the line of sight;
• wherein the first web is advanced toward the packaging station only when the signal from the product-sensing detector is of the second type.

A method for packaging products using continuous first and second webs of flexible packaging material, comprising the steps of:

• advancing the first web along a generally horizontal path toward a packaging station, and advancing the second web toward the packaging station such that the webs at the packaging station are in overlying relation and are sealed together with a product enclosed therebetween;
• receiving the product to be packaged onto an infeed conveyor belt at a product placement location upstream of the packaging station for conveying the product to the packaging station;
• and
• providing a product-sensing detector adjacent the infeed conveyor belt at or downstream of the product placement location and upstream of the packaging station such that the product-sensing detector has a direct line of sight to the infeed conveyor belt when no product is present on the infeed conveyor belt, the line of sight being blocked by the product when present on the infeed conveyor belt, the product-sensing detector being operable to detect a characteristic of the infeed conveyor belt distinct from the products being packaged and to provide a signal of a first type when said characteristic is detected and of a second type when said characteristic is not detected, indicating blockage of the line of sight;
• wherein the first and second webs are advanced toward the packaging station only when the signal from the product-sensing detector is of the second type.