Abstract: A cardiac pacer has separate digital filter circuits for sensing atrial and ventricular activity. Parameter data stored in memory is used by the digital filters for identifying the various components of cardiac activity, such as the P, R and T waves, as well as for identifying Premature Ventricular Contractions (PVC). A Ventricular Rate Time Out period is established from the last natural beat or stimulating pulse; and if a P wave or natural R wave is not sensed during that period, the system generates a stimulating pulse and, using T wave parameters in the ventricular filter, tests to verify capture. Loss of capture increases stimulating pulse width and amplitude to regain capture. If a P wave is sensed before the Rate Time Out period ends, the system establishes a predetermined P-R interval period to override the Ventricular Rate Time Out period in which the ventricular filter is set to detect a natural R wave in an effort to synchronize the ventricle with the atrium.

Abstract: A fishhook assembly has the characteristics of being weedless in its unactivated-rest-position by nature of the symmetrical configuration of the three or four identical fishhooks, each point of which is positioned to the outside of the assembly and guarded by an adjacent fishhook. Movement of the fishhook assembly from the unactivated-rest-position to the activated-snagging-position is imparted to the fishhook assembly by the closing of the fish's mouth, forcing the fishhook shanks toward a common central axis and exposing at least one fishhook point for snagging the fish.

Abstract: A heater vent having a temperature responsive damper such as a bimetallic element is disclosed. A shroud-like structure is positioned to cooperate with the temperature responsive element to close the vent at an elevated temperature and thereby reduce loss of residual heat while permitting the combustion gases to be completely purged from the firebox. For safety, movement of the temperature responsive element is uninhibited in all positions with complete vent closure occurring at ambient temperature and with the damper open during heater burner operation.

Abstract: Apparatus for combining light tillage and application of liquid fertilizer in a single implement includes a frame having at least a forward and a rear mounting bar. A plurality of sweep assemblies are mounted to the forward mounting bar. Anhydrous fertilizer applicator knives are mounted to the rear bar and located in strips left untilled by the sweeps. A finishing harrow is also mounted to the rear bar behind the knives to level the soil. Each sweep assembly includes a forward bar or frame element to which a plurality of laterally spaced sweeps are mounted in staggered relation. Mounting members having vertically elongated slots mount the sweep assemblies to the forward bar of the frame while permitting them to be adjusted vertically and independent of the depth of the applicator knives.

Abstract: A loading dock shelter for use around a doorway on wall, includes a flexible head cover panel, having top, bottom and side edges. Two sleeves, each sleeve secured to opposite side edges of the head panel to an intermediate area between the top and bottom edges, slidably receive two flexible elastic straps respectively. One end of each strap extends upward toward the top edge of the head panel and one end of each strap extends in a taut draped manner from the sleeve. The ends of the strap are secured in a stationary manner to the side frame member. The flexible elastic straps restrain and cushion the head panel as the head panel is subjected to outside forces reducing strain and wear, yet allowing the head curtain to yield upon engagement with a truck.

Abstract: A substantially rectangular-shaped building block, particularly well adapted for use in a set of identical toy building blocks, having a length, to width, to thickness ratio in the nature of 3 to 2 to 1, and having each of the four corner portions identical in cross-sectional size and shape to an indentation in the center portion of each of the four sides of the rectangle.

Abstract: A human reproduction indexing device for indicating the calendar dates for days of a menstrual cycle on which the probability of conception is the greatest includes a generally rectangular member having indicia representing the calendar dates for the days of given months positioned in three separate columns on the member and indicator-index columns aligned and positioned adjacent each of the separate columns on the member. When the calendar date corresponding to the day of the onset of the menses is known, the indicator-index columns indicate the calendar dates for an eight day interval starting ten days after the indexed date to provide the time interval during which ovulation should occur and thus the days on which the probability of conception are maximized.

Abstract: The planter includes a number of forward tillage units each followed by an aligned planting unit. Both units are independently mounted by four-bar linkages to the planter frame. Each tillage unit includes a leading banded coulter followed by a pair of rolling row cleaning discs which are, in turn, followed by a fluted coulter. The system may be used in any of the following planting modes: (1) no-till planting, in which the fluted coulter only is used to prepare a narrow band of soil for planting with no trash removal; (2) ridge planting or till-planting, in which the row cleaning discs clear a deeper wide band before the fluted coulter while leaving bands between the row crops untilled; (3) minimum tillage planting, in which the row cleaning discs may be used to clear a shallow band of surface trash before the fluted coulter; and (4) conventional planting, in which the tillage units are raised and not used.

Abstract: The system includes a damper plate equipped with a draft controller or sensing switch and a motor for positioning the damper plate to control the furnace draft. Upon generation of a call-for-heat signal, an initialization signal drives the damper off its closed position. From then on, draft must be sensed by the draft controller switch to complete the cycle to open the damper plate. When the damper plate is fully opened, a fuel and ignition control circuit is energized to supply fuel to the furnace, and an electronic timer is energized to generate a signal which establishes a trial-for-draft period. When the fuel is ignited, the draft will increase and energize the motor to move the damper plate off the fully open position during the trial-for-draft period, and thereafter, the position of the damper plate is controlled by the draft controller switch to achieve a proper draft within design range.

Abstract: A computer system is disclosed for preparing a complete set of architectural specifications for constructing a building, including, if desired, sets of instructions that will be used by personnel during preparation of construction drawings and during construction. A specifier uses brief symbolic characters representative of individual phrases from a large information repository called a Master Phrase Catalog, to mark decisions and phrase selections in code on an order form designed to facilitate the specifier's task. The information in the Master Phrase Catalog includes construction materials, techniques, reference information, testing and industry standards which are correlated with instructional information and work assignments for various groups of people. The specifier uses only a limited number of commands to completely specify a project.

Abstract: A tube support embodying a plurality of supporting members, each having grooved opposite side members with a crossbar extending therebetween, the supporting members being disposed in inter-locked relation to each other, with the crossbars being vertically spaced from each other to support tubular members thereon, and with the crossbars of upper supporting members extending down into the grooves in immediately underlying members.

Abstract: Brushes and the method of making the same by first forming a strip embodying a backing sheet with bristles disposed on one face thereof in parallel relation to each other and with ends projecting outwardly from one longitudinal edge of the strip; forming the strip into a predetermined shape; securing the aforementioned bristle ends in a base; and removing the backing sheet from the bristles.

Abstract: A container closure comprises an inner housing having means for sealably mounting to a container. A plurality of indicia are removably disposed in a relatively fixed stationary manner upon the inner housing. An outer housing is rotatably mounted to the inner housing and includes an aperture extending therethrough aligned with the indicia of the inner housing effective to pass the indicia past the aperture for viewing. One of the housings has a plurality of depressed grooves positioned upon its cylindrical walls. At least one rib on the other housing is engageable with at least one of the depressed grooves during the rotation of the outer housing and is restrained in a manner effective to stop the relative rotation of the housings in one direction, yet yieldingly resist rotation of the housings relative to each other in the opposite direction.

Abstract: A top-loaded low profile antenna for data transponders includes an antenna pin mounted vertically, affording vertical polarization for the antenna, an aluminum plate mounted in a horizontal plane and connected to an upper end of the pin, providing top-loading of the antenna, the plate being supported by a lucite frame mounted on an upper surface of the data transponder and which also dielectrically loads the antenna feed region. The load plate and lucite frame enclose the antenna pin so that the antenna is less susceptible to vandalism, and the top-loading results in a reduction in the height of the antenna structure improving the aesthetics of the antenna and data transponder installation.

Abstract: A gravity-actuated guide for row crops which mounts on a tractor front axle to enable the operator to compensate for changes in transverse slope by steering the tractor and thereby correctly position cultivating equipment behind the tractor in relation to the rows.

Abstract: Method of making multi-port heat exchangers wherein tubular members made of metal that does not well lend itself to being extruded into a plurality of passageways may be divided into multiple passageways by dividers inserted thereinto and adhered thereto.

Abstract: A billing recorder for providing a record of customer usage of electricity has a controller which may include a microprocessor for receiving and processing pulses from an electric meter. Data from one or more input channels is temporarily stored in random access memory by the controller in data words representative of energy consumed in predetermined time ("demand") intervals. The accumulated measurement ("event") data and time reference data are transferred to a non-volatile, solid state memory at the end of relatively long collection periods which comprise a number of demand intervals. The solid state preferably is energized by the controller only during data transfers. The entire memory module is removable for processing at a central location, and it is replaced with a new one when it is removed.

Abstract: When a call for heat is established, a flame relay is actuated for a predetermined time by means of a cycling timer. Upon this initial actuation, the flame relay inhibits a checking relay and initializes a trial-for-ignition (or simply "ignition") timer. After the cycling timer times out and the flame relay has been completely cycled, which establishes operativeness of the flame relay and flame sensing circuitry, the checking relay is enabled and actuated for the ignition period. The checking relay then actuates the pilot valve and a spark generator to start a pilot flame. If a flame is sensed, before the ignition timer times out, the flame relay actuates the main valve and establishes a holding current for the ignition timer so that the checking relay continues to be energized. If a flame is not sensed during the trial period, the ignition timer disables the checking relay, thereby de-energizing the pilot valve before the main valve is opened.

Abstract: A tire trimmer tool has an elongated handle and a U-shaped frame to which a blade of undulated sheet metal is detachably mounted. The undulations comprise closely-spaced parallel ridges which extend front and rear, are open on their underside and are united by narrow connecting webs. The undulations are arranged across the full width of the blade; and the outermost undulations which comprise the two sides of the blade have upturned walls, the edge of which seat is facing slots provided the legs of the U-frame; and an adjustable clamp which connects the two legs secures the blade in place. The fore end of the blade is sharpened on its underside and a narrow transverse portion of the blade therebehind is struck or turned upwardly across the full width of the blade and limits bowing of the blade in response to tightening of the clamp.

Abstract: A laminated structure includes a wafer member with a membrane attached thereto, the membrane being formed of substantially hydrogen-free boron nitride having a nominal composition B.sub.3 N. The structure may be a component in a mechanical device for effecting a mechanical function, or the membrane may form a masking layer on the wafer. The structure includes a body formed of at least two wafer members laminated together with a cavity formed therebetween, with the boron nitride membrane extending into the cavity so as to provide the structural component such as a support for a heating element or a membrane in a gas valve. In another aspect borom is selectively diffused from the boron nitride into a <100> surface of a silicon wafer. The surface is then exposed to EDP etchant to which the diffusion layer is resistant, thereby forming a channel the wafer member with smooth walls for fluid flow.