An object of the present invention is to provide a tensioner that enables a sufficient amount of stroke for the plunger to be secured and allows for size and weight reductions without changing the size of the tensioner body. In the tensioner according to the invention, an oil supply path that supplies oil from outside to an oil reservoir chamber formed inside the plunger includes an oil supply space formed between an inner circumferential surface of the plunger bore and an outer circumferential surface of the plunger. The oil supply space is formed by a front-end communication groove formed on an inner circumferential surface of the plunger bore and communicating with a tensioner body oil supply hole, and a rear-end communication groove formed on an outer circumferential surface of the plunger and causing the front-end communication groove to communicate with a plunger oil supply hole.

A belt tensioner for an engine accessory drive is installed over a pulley such that rollers extend toward the engine. Due the belt being between the tensioner and the engine, installation of the belt on the pulley is difficult. To simplify installation, a removable belt guide is included in the belt tensioner. Two methods of installing the belt and tensioner are envisioned. In a first method, the belt is first installed on the pulley and the belt guide holds the belt toward the pulley radially as the tensioner is installed over the pulley. In a second method, the belt is first installed to the tensioner and the guide holds the belt radially away from the pulley as the tensioner is installed over the pulley. In both methods, the belt guide is removed after the belt and tensioner are installed.

A belt tensioner for an engine accessory drive is installed over a pulley such that rollers extend toward the engine. Due the belt being between the tensioner and the engine, installation of the belt on the pulley is difficult. To simplify installation, a removable belt guide is included in the belt tensioner. Two methods of installing the belt and tensioner are envisioned. In a first method, the belt is first installed on the pulley and the belt guide holds the belt toward the pulley radially as the tensioner is installed over the pulley. In a second method, the belt is first installed to the tensioner and the guide holds the belt radially away from the pulley as the tensioner is installed over the pulley. In both methods, the belt guide is removed after the belt and tensioner are installed.

A variable force tensioner (VFT) system that includes a primary piston split into two chambers disposed within a primary bore. The two chambers including a first low pressure chamber having a primary reservoir therein that feeds fluid through a check valve into a second high pressure chamber to control a biasing force on the primary piston. A piston bore clearance path can extend along a groove in the primary bore to feed oil back to the primary reservoir from the high pressure chamber.

To provide a tensioner that can keep the oil pressure in an oil pressure chamber stable and consistently generate suitable reaction force and damping force to impact loads to reduce looseness in the chain and noise. A piston is set such as to partition an inner space of a plunger into an adjustment space on the front side and the oil pressure chamber on the rear side, a piston restricting member restricting the movement of the piston toward the adjustment space. An oil relief mechanism is configured to cause the piston to move forward when oil pressure in the oil pressure chamber rises so as to discharge oil inside the oil pressure chamber to the outside. The piston restricting member has an orifice function that can control the amount of discharged oil.

To provide a chain tensioner that can suppress oil leakage from a gap between a plunger bore and a plunger to achieve stable damping characteristics and that can avoid an increase in production cost, with a simple structure. The chain tensioner includes a packing member that is provided on an inner circumferential side of the plunger bore and that suppresses oil leakage from a cylindrical outer surface of the plunger. The plunger is provided with an oil leak passage that extends from an oil pressure chamber inside the plunger to the outside.

A tensioner includes a movable section, a fixed section, a flat spiral spring, and a back-up spring. The movable section receives load from an entrained transmission body through a tension member. The fixed section supports the movable section so as to be capable of displacing. The flat spiral spring biases the movable section so as to resist the tension member. The flat spiral spring unwinds in a state in which there is a small inter-plate friction force in cases in which there is a large biasing force applied to the tension member to counter load acting from the tension member. The flat spiral spring winds-up in a state in which there is a large inter-plate friction force in cases in which there is a small biasing force applied to the tension member to counter load acting from the tension member. The back-up spring limits wind-up of the flat spiral spring.

A debucking machine, for use with processing industrial hemp or cannabis, is provided. Embodiments of the debucking machine include counter-rotating rollers equipped with rubberized combs for gently removing flowers, or “buds,” from harvested industrial hemp or cannabis. Embodiments of the debucking machine are portable and may be moved from location to location within a drying shed.

An orifice member is disposed in a plunger including a plunger hole that forms a hydraulic chamber in conjunction with a plunger housing hole in a housing. The orifice member includes a deformed fitting section deformed to fit on the inner circumferential surface of the plunger hole, a communication section that causes a surface in contact with the top surface on the front side of the plunger hole and a surface on the hydraulic chamber side to communicate, and an orifice groove that communicates with the communication section and an external relief hole provided in the plunger on the surface in contact with the top surface on the front side of the plunger hole to constitute an orifice.

Transmission belt tensioner includes (a) a housing, (b) a set of disc springs, (c) a tensioning arm which is connected to the disc springs for compressing the disc springs upon a movement of the tensioning arm out of a neutral position in a deflection direction (A) relative to the housing. In an embodiment, a second set of disc springs is provided, wherein the tensioning arm is connected to the disc springs of the second set for compressing them upon a movement of the tensioning arm out of a neutral position in an opposite direction (G) to the deflection direction (A).