Patent Application
20130180495
The present invention relates to hand held equipments in general and lawn and garden equipment in particular. The current equipments, for example, trimmer, blowers, generators, cultivators, water pumps, etc, including go-peds all each have internal combustion engines or electric motors, which are either battery powered or electrical motors. Each equipment powered, particularly by the internal combustion engines more or less are all about the same power ratings and even operate within the same RPM ranges. The disadvantage to the customer is that not all the equipments are used year long and in most cases they are used seasonally. Sometimes, they are rarely used, such as the emergency power generators. As such, the disadvantages are that the consumer has to pay for each engine and have to maintain them regularly, whether the equipment is used or not. Secondly, the equipment typically carry about one to two years warranty, which means the warranty simply expires even if the engine is not used for the reasonable number of hours a year. Thirdly, each of the equipments mostly likely requires carburetor or fuel treatment for long term storage and annual maintenance. Also, in most cases, the lubricating oil in each of the engines, has a limited shelf life and need to be periodically changed. Changing the oil means expense and polluting the environment. As such, the real life cycle cost of each equipment is unnecessarily higher and wasteful. In most cases, the useful life of the engine is about 5 to 8 years and during the life of the engine, the emission standard typically become stringent. This means the older engines keep polluting even though cleaner engines are available in the market.
The present invention resolves many of the disadvantages described above. The present invention relates to detachable power head system where an engine or an electric motor could be attached and detached easily by the consumer to power any of the equipments, including but not limited to trimmer, blower, generator, back pack blower, water pump, sprayer, electric generator, chainsaw, etc, including go-peds. The embodiment consists of a mechanism where power heads are aligned with the locating groves on the equipment and fastened easily either by simple twist and lock or clamps or even bolt and nut type of fastening devices. The advantages are that the consumers need to purchase and maintain only one engine or a motor. There are, however, different attachments for a trimmer engine are available, such as a blower, tiller, edger etc that are attached to the upper boom. However, the attachments are not designed for optimum performance and become heavy, particularly when a blower or a cultivator attachment is attached to a trimmer engine having an upper boom. Whereas with the current invention, the blower, for example can be large and designed for best air flow and as good as dedicated blower. The engine or the motor in the case of the current invention can be attached to a cultivator or an edger on wheels, while getting the best performance out of the complete system. The power head can also contain fuel tank, lubricating tank, if separate, and starter assembly. An external electric start can be used to make the entire unit light weight and compact. When internal combustion engine is used to drive the equipment, it can be a four-stroke, two-stroke, or a rotary engine using either liquid or gaseous fuels. The engine can be either wet or dry lubricated or oil injected engine as in a two-stroke engine. The four-stroke engine may also be a mist lubricated as in Honda's trimmer or Stihl's pre-mix 4 stroke engine trimmer. The oil tank could be attached to the power head or to the equipment. The electric motor can be a corded or cordless battery operated motor or for that matter even an air powered motor. The secondary advantage with an universal type attachment mechanism is that any size engine or engine from different manufacturers can be used on a single equipment. Thus provides the consumer a variety of freedom to choose equipment and engines from different manufacturers. Also, with the advancement of the engine technologies, same equipment can be retained while upgrading only the engine. When an engine has to be thrown away in case the engine cannot be repaired, then the consumer can buy only the engine for lower cost and yet keep his or her old equipment. Thus the current invention is more earth friendly and sustainable.
The power head described here pertains to an internal combustion engine of two or four-stroke type and it may use any type of fuel, liquid or gaseous. Fuel delivery system can be carbureted or fuel injected type or a combination of fuel injection and carburetor (mixer) type. The power head shown in Figures in this invention is an internal combustion engine, but an electric or a compressed air powered motor can be used. In the present invention, a trimmer and a blower are shown, only as examples. It must be understood that many different types of equipments can used. The accompanying drawings show a power head 200, which is an internal combustion engine attached to an equipment, a trimmer 500 in this case is shown in
Advantages of the present invention will become more apparent to those skilled in the art from the following description of the preferred embodiments of the invention that have been shown and described by way of illustration. As will be realized, the invention is capable of other and different embodiments, and its details are capable of modification in various respects. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive.
The features and advantages of the present invention may be better understood by reference to the accompanying drawings in which like reference numerals refer to like elements.
While this invention is susceptible of several different embodiments, this specification and the accompanying drawings disclose only some specific forms as examples of the invention. The invention is not intended to be limited by the descriptions in this specification or the drawings. Instead, the scope of the invention is provided in the claims.
Embodiments in accordance with the present invention will be described below with references to
The key feature, as an example consists of rings one each ne the power head and the equipment. The ring 880 is an integral part of the housing 239 on the power head 200. The ring 239 can be fastened to the power head housing or can be an integral part of the housing. Similarly the ring 800 can be an integral part of the equipment or can be fastened to the housing of the equipment.
The ring 800 consists radial groves 812, which are multiple in number and are the radially cut outs of circumferential lip 808. The radial grove has vertical grove to guide the radial hook 830 on the ring 880 of the power head. The circumferential lip 808 has circumferential grove 814 into which the radial hook fits into when the ring 880 is twisted to lock position. Appropriate stop 816 is provided in the ring 800 to bring the two rings to proper final position where the kill switch contacts 209a and 209b are in position and in contact with each other. Similarly the throttle connector assembly 712 is aligned and in proper final position for actuation of the throttle in the fuel mixer when the throttle lever 221a is operated. The two rings 800 and 880 can be locked in position tool-lessly as better described in U.S. Pat. No. 5,918,574 for example. In the U.S. Pat. No. 5,918,574 is, however, used to lock the fuel container in position and not for the attachment and detachment of power head. Any similar connector devices can be used. Alternatively a simple V-band can be used to lock the two rings. For example V-band are used to lock the turbine and a compressor in an automobile turbo-charger. Alternatively clamps as used in suit cases or air filter covers can also be used. Nuts with wing nut where the bolt can swing open, while being hinged on the ring can also be used.
Typically, some equipment may need clutched operation so that the equipment is not operational when the power head is idling or running at very low RPM. For such applications, the equipment may have a clutch drum 216 such that the clutch 217 on the power head drives the equipment only above certain power RPM. However, in certain other types of equipment, blower for example may not need clutch. In that case the drive shaft 918 may engage the crankshaft 22a directly through the external and internal splines, 250 and 918 respectively. The clutch 217 may have a hub at the center having an internal spline. Alternatively the crankshaft 22a may have internal spline cut at the outer end.
The accompanying drawings for the power head have an outboard starter assembly 818, which consists of a pulley 816 and a rope 814 with the handle 812. However, the starter assembly can also be on the inboard side (near the flywheel 208). Alternatively, the power head may be completely devoid of any built in starter assembly, but may have an external starter (external to the power head, which is also a detachable type, as in the case of an MTD's trimmer, where an electric starter is employed to start the engine.
The following are embodiments, not claims:
A. A detachable power head (200) comprising:
The foregoing disclosure is the best mode devised by the inventors for practicing this invention. It is apparent, however, that apparatus incorporating modifications and variations will be obvious to one skilled in the art. Inasmuch as the foregoing disclosure is intended to enable one skilled in the pertinent art to practice the instant invention, it should not be construed to be limited thereby but should be construed to include aforementioned obvious variations and be limited only by the spirit and scope of the following claims.
It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention.
